| Dell™ Dimension™ 8400 Service Manual   Notes, Notices, and Cautions   NOTE: A NOTE indicates important information that helps you make better use of your computer.   NOTICE: A NOTICE indicates either potential damage to hardware or loss of data and tells you how to avoid the problem.   CAUTION: A CAUTION indicates a potential for property damage, personal injury, or death.   Abbreviations and Acronyms   For a complete list of abbreviations and acronyms, see the Dell Dimension Owner's Manual.   If you purchased a Dell™ n Series computer, any references in this document to Microsoft® Windows® operating systems are not applicable.   NOTE: Some features or services may not be available for your computer or in certain countries.   Information in this document is subject to change without notice.   © 2004 Dell Inc. All rights reserved.   Reproduction in any manner whatsoever without the written permission of Dell Inc. is strictly forbidden.   Trademarks used in this text: Dell, the DELL logo, and Dimension are trademarks of Dell Inc.; Intel and Pentium are registered trademarks of Intel Corporation; Microsoft and   Windows are registered trademarks of Microsoft Corporation.   Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell Inc. disclaims any   proprietary interest in trademarks and trade names other than its own.   Model DHM   November 2004   Rev. A00   Memory modules are detected, but   a memory failure has occurred.   l and then restart the computer. If the computer starts normally, reinstall an additional module.   Continue until you have identified a faulty module or reinstalled all modules without error.   If available, install properly working memory of the same type into your computer.   If the problem persists, contact Dell.   l l A possible graphics card failure has   occurred.   l l l and then restart the computer.   If the problem still exists, install a graphics card that you know works and restart the   computer.   If the problem persists or the computer has integrated graphics, contact Dell.   A possible floppy or hard drive   failure has occurred.   Reseat all power and data cables and restart the computer.   A possible USB failure has   occurred.   Reinstall all USB devices, check cable connections, and then restart the computer.   No memory modules are detected.   l and then restart the computer. If the computer starts normally, reinstall an additional module.   Continue until you have identified a faulty module or reinstalled all modules without error.   If available, install properly working memory of the same type into your computer.   If the problem persists, contact Dell.   l l Memory modules are detected, but   a memory configuration or   compatibility error exists.   l l l Ensure that no special memory module/memory connector placement requirements exist (see   Verify that the memory modules that you are installing are compatible with your computer (see   If the problem persists, contact Dell.   A possible expansion card failure   has occurred.   restarting the computer.   2. If the problem persists, reinstall the card that you removed, remove a different card, and then   restart the computer.   3. Repeat this process for each card. If the computer starts normally, troubleshoot the last card   removed from the computer for resource conflicts.   4. If the problem persists, contact Dell.   Another failure has occurred.   l l l drive, and DVD drive.   If there is an error message on your screen identifying a problem with a device (such as the   floppy drive or hard drive), check the device to make sure it is functioning properly.   The operating system is attempting to boot from a device (such as the floppy drive or hard   for the devices installed on your computer.   l If the problem persists, contact Dell.   The computer is in a normal   None.   operating condition after POST.   Beep Codes   Your computer might emit a series of beeps during start-up if the monitor cannot display errors or problems. This series of beeps, called a beep code, identifies   a problem. One possible beep code (code 1-3-1) consists of one beep, a burst of three beeps, and then one beep. This beep code tells you that the computer   encountered a memory problem.   Reseating the memory modules may fix the beep code errors in the following table. If the problem persists, see "Contacting Dell" in your Owner's Manual for   instructions on obtaining technical assistance.   Code   1-3-1 through 2-4-4 Memory not being properly identified or used   4-3-1 Memory failure above address 0FFFFh   Cause   If you hear one of the following beep codes, see "Contacting Dell" in your Owner's Manual for instructions on obtaining technical assistance.   Code Cause   1-1-2 Microprocessor register failure   1-1-3 NVRAM   1-1-4 ROM BIOS checksum failure   1-2-1 Programmable interval timer   1-2-2 DMA initialization failure   1-2-3 DMA page register read/write failure   3-1-1 Slave DMA register failure   3-1-2 Master DMA register failure   3-1-3 Master interrupt mask register failure   3-1-4 Slave interrupt mask register failure   3-2-2 Interrupt vector loading failure   3-2-4 Keyboard Controller Test failure   3-3-1 NVRAM power loss   3-3-2 NVRAM configuration   3-3-4 Video Memory Test failure   3-4-1 Screen initialization failure   3-4-2 Screen retrace failure   3-4-3 Search for video ROM failure   4-2-1 No time tick   4-2-2 Shutdown failure   4-2-3 Gate A20 failure   4-2-4 Unexpected interrupt in protected mode   4-3-3 Timer-chip counter 2 failure   4-3-4 Time-of-day clock stopped   4-4-1 Serial or parallel port test failure   4-4-4 Cache test failure   System Messages   NOTE: If the message you received is not listed in the table, see the documentation for either the operating system or the program that was running   when the message appeared.   Message   Possible Cause   Corrective Action   8042 Gate-A20   error   The keyboard controller failed If you receive this message after you   its test.   make changes in the system setup   program, enter the system setup   program and restore the original value   (s).   Address Line   Short!   An error in the address   decoding circuitry in the   memory has occurred.   C: Drive Error   The hard drive is not working Ensure that the drive is installed   or is not configured correctly.   correctly in the computer and defined   C: Drive Failure   Cache Memory   Bad, Do Not   Enable Cache   The cache memory is not   operating.   See "Contacting Dell" in your Owner's   Manual for instructions on obtaining   technical assistance.   CH-2 Timer Error An error is occurring on the   See "Contacting Dell" in your Owner's   Manual for instructions on obtaining   technical assistance.   timer on the system board.   CMOS Battery   State Low   The system configuration   information in the system   setup program is incorrect or   the battery charge may be   low.   the system configuration, and then   restart the computer.   CMOS Checksum   Failure   CMOS System   Options Not Set   CMOS Display   Type Mismatch   CMOS Memory Size   Mismatch   CMOS Time and   Date Not Set   Diskette Boot   Failure   Drive A or B is present but   has failed the BIOS POST.   Ensure that the drive is installed   correctly in the computer and defined   Check the interface cable at both ends.   DMA Error   the system board. to be replaced.   DMA 1 Error   DMA 2 Error   FDD Controller   Failure   with the floppy drive or hard   drive controller.   computer and defined correctly in the   system setup program. Check the   interface cable at both ends.   HDD Controller   Failure   INTR1 Error   INTR2 Error   An interrupt channel on the   system board failed to POST.   to be replaced.   Invalid Boot   Diskette   be located on drive A or drive confirm that drive A or drive C is properly   C.   identified.   Keyboard Error   The BIOS has detected a   stuck key.   Ensure that nothing is resting on the   keyboard; if a key appears to be stuck,   carefully pry it up. If the problem   persists, you may need to replace the   keyboard.   KB/Interface   Error   An error occurred with the   keyboard connector.   Ensure that nothing is resting on the   keyboard; if a key appears to be stuck,   carefully pry it up. If the problem   persists, you may need to replace the   keyboard.   No ROM Basic   be located on drive A or drive confirm that drive A or drive C is properly   C.   identified.   Before You Begin   Dell™ Dimension™ 8400 Service Manual   Getting Started   This section provides procedures for removing and installing the components in your computer. Unless otherwise noted, each procedure assumes that the   following conditions exist:   l l l You have performed the steps in "Turning Off Your Computer" and "Before Working Inside Your Computer."   You have read the safety information in your Dell™ Product Information Guide.   A component can be replaced by performing the removal procedure in reverse order.   Recommended Tools   The procedures in this document may require the following tools:   l l l Small flat-blade screwdriver   Phillips screwdriver   Flash BIOS update program floppy or CD   Turning Off Your Computer   NOTICE: To avoid losing data, save and close any open files and exit any open programs before you turn off your computer.   1. Shut down the operating system:   a. Save and close any open files, exit any open programs, click the Start button, and then click Turn Off Computer.   b. In the Turn off computer window, click Turn off.   The computer turns off after the operating system shutdown process finishes.   2. Ensure that the computer and any attached devices are turned off. If your computer and attached devices did not automatically turn off when you shut   down your operating system, press and hold the power button for 4 seconds.   Before Working Inside Your Computer   Use the following safety guidelines to help protect your computer from potential damage and to help ensure your own personal safety.   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: Handle components and cards with care. Do not touch the components or contacts on a card. Hold a card by its edges or by its metal   mounting bracket. Hold a component such as a processor by its edges, not by its pins.   NOTICE: Only a certified service technician should perform repairs on your computer. Damage due to servicing that is not authorized by Dell is not   covered by your warranty.   NOTICE: When you disconnect a cable, pull on its connector or on its strain-relief loop, not on the cable itself. Some cables have a connector with   locking tabs; if you are disconnecting this type of cable, press in on the locking tabs before you disconnect the cable. As you pull connectors apart, keep   them evenly aligned to avoid bending any connector pins. Also, before you connect a cable, ensure that both connectors are correctly oriented and   aligned.   NOTICE: To avoid damaging the computer, perform the following steps before you begin working inside the computer.   NOTICE: To disconnect a network cable, first unplug the cable from your computer and then unplug it from the network device.   2. Disconnect any telephone or telecommunication lines from the computer.   3. Disconnect your computer and all attached devices from their electrical outlets, and then press the power button to ground the system board.   CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before opening the cover.   NOTICE: Before touching anything inside your computer, ground yourself by touching an unpainted metal surface, such as the metal at the back of the   computer. While you work, periodically touch an unpainted metal surface to dissipate any static electricity that could harm internal components.   Opening the Computer Cover   Dell™ Dimension™ 8400 Service Manual   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before opening the cover.   NOTICE: Ensure that sufficient space exists to support the open cover—at least 30 cm (1 ft) of desk top space.   2. Lay the computer on its side so that the arrow on the bottom of the computer points up.   3. Open the cover:   a. Facing the back of the computer, press the release button on the right side of the computer with one hand while pulling up on the top of the   cover with the other hand.   b. Press the release button on the left side of the computer with one hand while pulling up on the top of the cover with the other hand.   c. Hold the bottom of the computer with one hand, and then pull open the cover with the other hand.   Closing the Computer Cover   Dell™ Dimension™ 8400 Service Manual   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   1. Ensure that all cables are connected, and fold cables out of the way.   Gently pull the power cables toward you so that they do not get caught underneath the drives.   2. Ensure that no tools or extra parts are left inside the computer.   3. Close the cover:   a. Pivot the cover down.   b. Press down on the right side of the cover until it closes.   c. Press down on the left side of the cover until it closes.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   4. Connect your computer and devices to electrical outlets, and turn them on.   Removing and Installing Parts   Dell™ Dimension™ 8400 Service Manual   Memory   You can increase your computer memory by installing memory modules on the system board.   Your computer supports DDR2 memory. For additional information on the type of memory supported by your computer, see "Memory".   DDR2 Memory Overview   DDR2 memory modules should be installed in pairs of matched memory size, speed, and technology. If the DDR2 memory modules are not installed in matched   pairs, the computer will continue to operate, but with a slight reduction in performance. See the label on the upper-right corner of the module to determine the   module's capacity.   NOTE: Always install DDR2 memory modules in the order indicated on the system board.   The recommended memory configurations are:   ¡ A pair of matched memory modules installed in DIMM connectors 1 and 2   or   ¡ A pair of matched memory modules installed in DIMM connectors 1 and 2 and another matched pair installed in DIMM connectors 3 and 4   NOTICE: Do not install ECC memory modules.   l l If you install mixed pairs of DDR2 400-MHz (PC2-3200) and DDR2 533-MHz (PC2-4200) memory, the modules function at the slowest speed installed.   Similarly, if you install memory modules with mixed CAS Latency (CL) rates, the modules function at the speed and CAS latency capabilities of the   slowest DIMM.   Be sure to install a single memory module in DIMM connector 1, the connector closest to the processor, before you install modules in the other   connectors.   NOTE: Memory purchased from Dell is covered under your computer warranty.   NOTICE: If you remove your original memory modules from the computer during a memory upgrade, keep them separate from any new modules that   you may have, even if you purchased the new modules from Dell. If possible, do not pair an original memory module with a new memory module.   Otherwise, your computer may not start properly. You should install your original memory modules in pairs either in DIMM connectors 1 and 2 or DIMM   connectors 3 and 4.   Addressing Memory With 4-GB Configurations   Your computer supports a maximum of 4 GB of memory when you use four 1-GB DIMMs. Current operating systems, such as Microsoft® Windows® XP, can   only use a maximum of 4 GB of address space; however, the amount of memory available to the operating system is less than 4 GB. Certain components   within the computer require address space in the 4-GB range. Any address space reserved for these components cannot be used by computer memory.   Installing Memory   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   NOTICE: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your   computer's electronic components. You can do so by touching an unpainted metal surface on the computer chassis.   2. Lay the computer on its side so that the system board is on the bottom of the inside of the computer.   3. Press out the securing clip at each end of the memory module connector.   4. Align the notch on the bottom of the module with the crossbar in the connector.   NOTICE: To avoid damage to the memory module, press the module straight down into the connector while you apply equal force to each end of the   module.   5. Insert the module into the connector until the module snaps into position.   If you insert the module correctly, the securing clips snap into the cutouts at each end of the module.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   7. Connect your computer and devices to electrical outlets, and turn them on.   8. Right-click the My Computer icon and click Properties.   9. Click the General tab.   10. To verify that the memory is installed correctly, check the amount of memory (RAM) listed.   Removing Memory   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   NOTICE: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your   computer's electronic components. You can do so by touching an unpainted metal surface on the computer chassis.   2. Press out the securing clip at each end of the memory module connector.   3. Grasp the module and pull up.   If the module is difficult to remove, gently ease the module back and forth to remove it from the connector.   Cards   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   NOTICE: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your   computer's electronic components. You can do so by touching an unpainted metal surface on the computer chassis.   Your Dell™ computer provides the following slots for PCI and PCI Express cards:   l l l Three PCI card slots   One PCI Express x16 card slot   One PCI Express x1 card slot   PCI Cards   If you are installing or replacing a card, follow the procedures in the next section. If you are removing but not replacing a PCI card, see "Removing a PCI Card."   If you are replacing a card, remove the current driver for the card from the operating system.   Installing a PCI Card   2. Press the lever on the card retention arm and raise the retention arm.   3. If you are installing a new card, remove the filler bracket to create a card-slot opening. Then continue with step 5.   4. If you are replacing a card that is already installed in the computer, remove the card.   If necessary, disconnect any cables connected to the card. Grasp the card by its top corners, and ease it out of its connector.   5. Prepare the card for installation.   See the documentation that came with the card for information on configuring the card, making internal connections, or otherwise customizing it for your   computer.   CAUTION: Some network adapters automatically start the computer when they are connected to a network. To guard against electrical shock, be   sure to unplug your computer from its electrical outlet before installing any cards.   6. Place the card in the connector and press down firmly. Ensure that the card is fully seated in the slot.   7. Before you lower the retention arm, ensure that:   l l The tops of all cards and filler brackets are flush with the alignment bar.   The notch in the top of the card or filler bracket fits around the alignment guide.   8. Press the retention arm into place, securing the card(s) in the computer.   NOTICE: Do not route card cables over or behind the cards. Cables routed over the cards can prevent the computer cover from closing properly or   cause damage to the equipment.   9. Connect any cables that should be attached to the card.   See the documentation for the card for information about the card's cable connections.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   10. Close the computer cover, reconnect the computer and devices to electrical outlets, and then turn them on.   11. If you installed a sound card:   b. Connect external audio devices to the sound card's connectors. Do not connect external audio devices to the microphone, speaker/headphone,   or line-in connectors on the back panel.   12. If you installed an add-in network adapter and want to disable the integrated network adapter:   b. Connect the network cable to the add-in network adapter's connectors. Do not connect the network cable to the integrated connector on the   back panel.   13. Install any drivers required for the card as described in the card documentation.   Removing a PCI Card   2. Press the lever on the card retention arm and raise the retention arm.   3. If necessary, disconnect any cables connected to the card.   4. Grasp the card by its top corners, and ease it out of its connector.   5. If you are removing the card permanently, install a filler bracket in the empty card-slot opening.   If you need a filler bracket, contact Dell.   NOTE: Installing filler brackets over empty card-slot openings is necessary to maintain FCC certification of the computer. The brackets also keep dust   and dirt out of your computer.   6. Lower the retention arm and press it into place, securing the card(s) in the computer.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   7. Close the computer cover, reconnect the computer and devices to electrical outlets, and then turn them on.   8. Remove the card's driver from the operating system.   9. If you removed a sound card:   b. Connect external audio devices to the audio connectors on the back panel of the computer.   10. If you removed an add-in network connector:   b. Connect the network cable to the integrated connector on the back panel of the computer.   PCI Express Cards   Your computer supports one PCI Express x16 card and one PCI Express x1 card.   NOTICE: PCI Express graphics cards that run higher than 75 W may require an additional cooling fan. Otherwise, your card could overheat and damage   your computer.   If a card fan is not present in your computer and you are installing a graphics card that runs at 75 W or higher, contact Dell to find out how to purchase a card   fan.   If you are installing or replacing a PCI Express card, follow the procedures in the next section. If you are removing but not replacing a card, see "Removing a   If you are replacing a card, remove the current driver for the card from the operating system.   Installing a PCI Express Card   2. Press the lever on the card retention arm and raise the retention arm.   3. If you are installing a new card, remove the filler bracket to create a card-slot opening. Then continue with step 5.   4. If you are replacing a card that is already installed in the computer, remove the card.   If necessary, disconnect any cables connected to the card. If your card includes a retention mechanism, remove the top of the retention mechanism by   pressing the tab and pulling up on the top. Gently pull the securing tab, grasp the card by its top corners, and then ease it out of its connector.   5. Prepare the card for installation.   See the documentation that came with the card for information on configuring the card, making internal connections, or otherwise customizing it for your   computer.   CAUTION: Some network adapters automatically start the computer when they are connected to a network. To guard against electrical shock, be   sure to unplug your computer from its electrical outlet before installing any cards.   6. If you are installing the card into the x16 card connector, position the card so the securing slot is aligned with the securing tab, and gently pull the   securing tab.   7. Place the card in the connector and press down firmly. Ensure that the card is fully seated in the slot   8. If you replaced a card that was already installed in the computer and you removed the top of the retention mechanism, you may reinstall the top.   9. Before you lower the retention arm, ensure that:   l l The tops of all cards and filler brackets are flush with the alignment bar.   The notch in the top of the card or filler bracket fits around the alignment guide.   10. Press the retention arm into place, securing the card(s) in the computer.   NOTICE: Do not route card cables over or behind the cards. Cables routed over the cards can prevent the computer cover from closing properly or   cause damage to the equipment.   If a card fan is not present in your computer and you are installing a graphics card that runs higher than 75 W, contact Dell to find out how to purchase a card   fan.   11. If you installed a PCI Express graphics card that runs at 75 W or higher, install the card fan. Contact Dell to find out how to purchase a card fan.   12. Connect any cables that should be attached to the card.   See the documentation that came with the card for information about the card's cable connections.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   13. Close the computer cover, reconnect the computer and devices to electrical outlets, and then turn them on.   14. If you installed a sound card:   b. Connect external audio devices to the sound card's connectors. Do not connect external audio devices to the microphone, speaker/headphone,   or line-in connectors on the back panel.   15. If you installed an add-in network adapter and want to disable the integrated network adapter:   b. Connect the network cable to the add-in network adapter's connectors. Do not connect the network cable to the integrated connector on the   back panel.   16. Install any drivers required for the card as described in the card documentation.   Removing a PCI Express Card   2. Press the lever on the card retention arm and raise the retention arm.   3. If necessary, disconnect any cables connected to the card.   4. If your card includes a retention mechanism, remove the top of the retention mechanism by pressing the tab and pulling up on the top.   5. Gently pull back the securing tab, grasp the card by its top corners, and then ease it out of its connector.   6. If you are removing the card permanently, install a filler bracket in the empty card-slot opening.   If you need a filler bracket, contact Dell.   NOTE: Installing filler brackets over empty card-slot openings is necessary to maintain FCC certification of the computer. The brackets also keep dust   and dirt out of your computer.   7. Lower the retention arm and press it into place, securing the card(s) in the computer.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   8. Close the computer cover, reconnect the computer and devices to electrical outlets, and then turn them on.   9. Remove the card's driver from the operating system.   10. If you removed a sound card:   b. Connect external audio devices to the audio connectors on the back panel of the computer.   11. If you removed an add-in network connector:   b. Connect the network cable to the integrated connector on the back panel of the computer.   12. Install any drivers required for the card as described in the card documentation.   Drives   Your computer supports a combination of these devices:   l l l Up to two hard drives   One optional floppy drive   Up to two CD or DVD drives   General Installation Guidelines   Connect serial ATA hard drives and serial CD/DVD drives to the system board connectors labeled SATA-0, SATA-1, SATA-2, or SATA-3. Connect IDE CD/DVD   drives to the connector labeled PRI IDE.   When you connect two IDE devices to a single IDE interface cable and configure them for the cable select setting, the device attached to the last connector on   the interface cable is the primary or the boot device (drive 0), and the device attached to the middle connector on the interface cable is the secondary device   (drive 1). See the drive documentation in your upgrade kit for information on configuring devices for the cable select setting.   Connecting Drive Cables   When you install a drive, you connect two cables—a DC power cable and a data cable—to the back of the drive and to the system board. Some drives may   also have an audio connector; one end of the audio cable attaches to the drive connector and the other end attaches to the system board.   Drive Interface Connectors   Serial ATA Connector   Most interface connectors are keyed for correct insertion; that is, a notch or a missing pin on one connector matches a tab or a filled-in hole on the other   connector.   When you connect an IDE cable, ensure that you align the colored stripe with the pin 1 connector. When you disconnect an IDE cable, grasp the colored pull   tab and pull until the connector detaches.   When you connect and disconnect a serial ATA cable, hold the cable by the connector at each end.   NOTE: The system board serial ATA connector may have an attached cover or shroud.   Power Cable Connector   Hard Drive   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before opening the cover.   NOTICE: To avoid damage to the drive, do not set it on a hard surface. Instead, set the drive on a surface, such as a foam pad, that will sufficiently   cushion it.   1. If you are replacing a hard drive that contains data you want to keep, back up your files before you begin to remove the hard drive.   Removing a Hard Drive   1. Disconnect the power and data cable from the drive and from the system board.   2. Press in on the tabs on each side of the drive and slide the drive up and out.   Installing a Hard Drive   1. Unpack the replacement hard drive, and prepare it for installation.   2. Check the documentation for the drive to verify that it is configured for your computer.   3. If your replacement hard drive does not have the bracket rails attached, remove the rails from the old drive by removing the two screws that secure   each rail to the drive. Attach the bracket rails to the new drive by aligning the screw holes on the drive with the screw holes on the bracket rails and   then inserting and tightening all four screws (two screws on each rail).   4. Install the hard drive into the computer by gently sliding the drive into place until you hear it securely click.   6. Check all connectors to be certain that they are properly cabled and firmly seated.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   8. Connect your computer and devices to electrical outlets, and turn them on.   See the documentation that came with the drive for instructions on installing any software required for drive operation.   9. If the drive you just installed is the primary drive, insert a bootable floppy disk into drive A.   10. Turn on the computer.   12. Exit system setup, and restart the computer.   13. Partition and logically format your drive before you proceed to the next step.   See the documentation for your operating system for instructions.   14. Test the hard drive by running the Dell Diagnostics.   15. If the drive you just installed is the primary drive, install your operating system on the hard drive.   Adding a Second Hard Drive   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before opening the cover.   NOTICE: To avoid damage to the drive, do not set it on a hard surface. Instead, set the drive on a surface, such as a foam pad, that will sufficiently   cushion it.   1. Check the documentation for the drive to verify that it is configured for your computer.   3. Remove the two plastic rails from the inside of the hard-drive bay by gently pulling the rails up and out of the bay.   4. Attach the rails to the hard drive using the two screws attached to the rails.   Ensure that the rail tabs are positioned at the back of the hard drive.   NOTICE: Do not install any drive into the lower hard-drive bay until you have removed the green drive rails from the inside of the hard-drive bay.   5. Remove the first hard drive from the upper bay and install it in the lower bay:   a. Disconnect the power and the data cable from the back of the first hard drive.   b. Press in the two rail tabs and pull the first hard drive out of the upper bay.   c. Gently slide the first hard drive into the lower bay until you hear a click.   d. Reconnect the power and data cable to the back of the first hard drive.   6. Gently slide the new hard drive into the upper bay until you hear a click.   7. Connect a power cable to the drive.   9. Close the computer cover.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   10. Connect your computer and devices to their electrical outlets, and turn them on.   See the documentation that came with the drive for instructions on installing any software required for drive operation.   Front-Panel Inserts   If you are installing a new floppy or CD/DVD drive instead of replacing a drive, remove the front-panel inserts.   1. Open the cover to a 90-degree angle.   2. Locate the insert that is in front of the drive bay that you want to use.   3. From inside the computer, press in the release tab of the insert.   4. From the outside of the computer, pull the insert away from the computer's front panel.   5. Remove the insert from the insert frame by pressing on the four tabs.   6. Reattach the empty insert frame over the front of the drive bay.   The insert frame fits only one way.   a. Face the front of the computer and slip the left side of the insert in to the left side of the drive bay opening.   b. Slightly press the right-side insert release tab and gently push in the insert.   If you are adding a floppy drive and you purchased the drive from Dell, you received a front panel insert in your floppy drive kit. Attach this insert over the front   of the drive bay.   If you are adding a floppy drive that was not purchased from Dell, reattach the empty insert frame over the front of the drive bay.   Floppy Drive   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before opening the cover.   Removing a Floppy Drive   1. Disconnect the power and data cables from the back of the floppy drive.   2. Disconnect the other end of the data cable from the system board.   3. Press inward on the two tabs on the sides of the drive, slide the drive upward, and then remove it from the floppy-drive bay.   Installing a Floppy Drive   1. If you are replacing a drive and the new drive does not have the bracket rails attached, remove the rails from the old drive by removing the two screws   that secure each rail to the drive. Attach the bracket to the new drive by aligning the screw holes on the drive with the screw holes on the bracket rails   and then inserting and tightening all four screws (two screws on each rail).   2. Gently slide the drive into place until the tabs securely click into position.   3. Attach the power and data cables to the floppy drive.   5. If you are installing a new floppy drive rather than replacing a drive, remove the front-panel inserts.   6. Check all cable connections, and fold cables out of the way to provide airflow for the fan and cooling vents.   NOTICE: To connect a network cable, first plug the cable in to the network device and then plug it in to the computer.   8. Connect your computer and devices to their electrical outlets, and turn them on.   See the documentation that came with the drive for instructions on installing any software required for drive operation.   10. Verify that your computer works correctly by running the Dell Diagnostics.   CD/DVD Drive   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before opening the cover.   Removing a CD/DVD Drive   2. Disconnect the power and data cables from the back of the drive.   3. Press inward on the two tabs on the sides of the drive, and then slide the drive upward and remove it from the drive bay.   Installing a CD/DVD Drive   1. If you are installing a new drive, unpack the drive and prepare it for installation.   Check the documentation that accompanied the drive to verify that the drive is configured for your computer. If you are installing an IDE drive, configure   the drive for the cable select setting.   2. Connect the new drive to the set of rails that are attached to the inside of the cover. If a set of rails is not attached inside the cover, contact Dell.   3. If you are installing a replacement drive and the new drive does not have the bracket rails attached, remove the rails from the old drive by removing the   two screws that secure each rail to the drive. Attach the bracket to the new drive by aligning the screw holes on the drive with the screw holes on the   bracket rails and then inserting and tightening all four screws (two screws on each rail).   4. Gently slide the drive into place until the tabs securely click into position.   5. Connect the power and data cables to the drive.   7. Check all cable connections, and fold cables out of the way to provide airflow for the fan and cooling vents.   NOTICE: To connect a network cable, first plug the cable in to the network device and then plug it in to the computer.   9. Connect your computer and devices to their electrical outlets, and turn them on.   See the documentation that came with the drive for instructions on installing any software required for drive operation.   11. Verify that your computer works correctly by running the Dell Diagnostics.   Airflow Shroud   Removing the Airflow Shroud   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.   2. Disconnect the cooling fan power cable from the fan connector on the system board.   3. Disconnect the power cable from the power connector on the system board.   4. Lift up the airflow shroud.   Processor   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.   NOTICE:   CAUTION: The heat sink can get very hot during normal operation. Be sure that the heat sink has had sufficient time to cool before you touch it.   2. Remove the heat sink:   a. Remove the retention module clips. Press the tabs toward the center of the clip and lift up.   b. On the retention base locate the tab opposite the power supply. Press on the retention base tab until the heat sink pops up slightly.   c. Press out on the second retention tab while lifting the heat sink up and out of the retention base.   NOTICE: Lay the heat sink down on its side.Do not touch or remove the thermal grease on the bottom of the heat sink.   NOTICE: If you are installing a processor upgrade kit from Dell, discard the original heat sink. If you are not installing a processor upgrade kit from Dell,   reuse the original heat sink and blower when you install your new processor.   3. Push down and out on the socket release lever.   4. Open the processor cover.   5. To remove the processor from the socket, lift the processor vertically in one motion.   Leave the release lever extended in the release position so that the socket is ready for the new processor.   Installing the Processor   NOTICE: Ground yourself by touching an unpainted metal surface on the back of the computer.   1. Unpack the new processor.   NOTICE: You must position the processor correctly in the socket to avoid permanent damage to the processor and the computer when you turn on the   computer.   2. If the release lever on the socket is not fully extended, move it to that position.   3. Align the pin-1 corners of the processor and socket.   NOTICE: To avoid damage, ensure that the processor aligns properly with the socket, and do not use excessive force when you install the processor.   NOTICE: Be careful not to touch or bend the pins on the system board.   4. Set the processor lightly in the socket and ensure that the processor is level in the socket. When the processor is positioned correctly, press it with   minimal pressure to seat it.   5. When the processor is fully seated in the socket, close the processor cover.   Ensure that the tab on the processor cover is positioned underneath the center cover latch on the socket.   6. Pivot the socket release lever back toward the socket and snap it into place to secure the processor.   NOTICE: If you are not installing a processor upgrade kit from Dell, reuse the original heat sink assembly when you replace the processor.   If you installed a processor replacement kit from Dell, return the original heat sink assembly and processor to Dell in the same package in which your   replacement kit was sent.   7. Install the heat sink:   a. Slide one end of the heat sink under the retention tab.   b. Pull out the other retention tab and lower the heat sink until it fits securely in the base.   NOTICE: Ensure the heat sink is correctly seated and secure.   8. Reinstall the retention module clips.   9. Lower the airflow shroud over the heat sink.   10. Reconnect the cooling fan power cable to the fan connector on the system board.   11. Reconnect the power cable to the power connector on the system board.   NOTICE: To connect a network cable, first plug the cable into the network wall jack and then plug it into the computer.   13. Connect your computer and devices to electrical outlets, and turn them on.   System Board   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of   your computer's electronic components. You can do so by touching an unpainted metal surface on the computer chassis.   NOTICE: The system board and metal tray are connected and are removed as one piece.   Removing the System Board   3. Remove any components that restrict access to the system board.   4. Disconnect all cables from the system board.   5. Before you remove the existing system board assembly, visually compare the replacement system board to the existing system board to make sure that   you have the correct part.   6. Remove the system board screw.   7. Pull up on the two tabs, slide the system board assembly toward the front of the computer, and then lift the asembly up and away.   8. Place the system board assembly that you just removed next to the replacement system board.   Replacing the System Board   1. Transfer components from the existing system board to the replacement system board:   b. Install them on the replacement board.   CAUTION: The processor package and heat-sink assembly can get hot. To avoid burns, ensure that the package and assembly have had sufficient   time to cool before you touch them.   c. Remove the heat-sink assembly and processor from the existing system board and transfer them to the replacement system board.   2. Configure the settings of the replacement system board.   3. Set the jumpers on the replacement system board so they are identical to the ones on the existing board.   NOTE: Some components and connectors on the replacement system board may be in different locations than the corresponding connectors on the   existing system board.   4. Orient the replacement board by aligning the notches on the bottom of the board with the tabs on the computer.   5. Slide the system board assembly toward the back of the computer until the assembly clicks into position.   6. Replace any components and cables that you removed from the system board.   7. Reconnect all cables to their connectors at the back of the computer.   NOTICE: To connect a network cable, first plug the cable into the network wall jack and then plug it into the computer.   9. Connect your computer and devices to electrical outlets, and turn them on.   Power Supply   Removing the Power Supply   NOTICE: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your   computer's electronic components. You can do so by touching an unpainted metal surface on the computer chassis.   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   2. Disconnect the DC power cables from the system board and the drives.   Note the routing of the DC power cables underneath the tabs in the computer frame as you remove them from the system board and drives. You must   route these cables properly when you replace them to prevent their being pinched or crimped.   3. Remove the two screws that attach the power supply to the back of the computer frame.   4. Press the release button located on the floor of the computer frame.   5. Slide the power supply toward the front of the computer approximately 1 inch.   6. Lift the power supply up and out of the computer.   Replacing the Power Supply   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   1. Slide the power supply into place.   2. Replace the two screws that secure the power supply to the back of the computer frame.   3. Reconnect the DC power cables.   4. Connect the AC power cable to the connector.   5. Run the cables underneath the clips, and press the clips to close them over the cables.   NOTICE: To connect a network cable, first plug the cable into the network wall jack and then plug it into the computer.   7. Connect your computer and devices to electrical outlets, and turn them on.   Battery   Replacing the Battery   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   NOTICE: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your   computer's electronic components. You can do so by touching an unpainted metal surface on the computer chassis.   A coin-cell battery maintains computer configuration, date, and time information. The battery can last several years.   If you have to repeatedly reset time and date information after turning on the computer, replace the battery.   CAUTION: A new battery can explode if it is incorrectly installed. Replace the battery only with the same or equivalent type recommended by the   manufacturer. Discard used batteries according to the manufacturer's instructions.   To replace the battery:   4. Remove the battery by pressing on the tab, which will release the battery from the battery socket.   5. Insert the new battery into the socket with the side labeled "+" facing up, and snap the battery into place.   6. Close the computer cover.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   7. Connect your computer and devices to electrical outlets, and turn them on.   9. Properly dispose of the old battery. See the Product Information Guide for battery disposal information.   Specifications   Dell™ Dimension™ 8400 Service Manual   Processor   Processor type   Intel® Pentium® 4 with HT Technology   NOTE: Not all Pentium 4 processors support Hyper-   Threading technology.   Level 1 (L1) cache   16 KB   Level 2 (L2 or L3) cache   512 KB, 1 MB, or 2 MB (depending on your computer   configuration) pipelined-burst, eight-way set   associative, write-back SRAM   Memory   Type   400- and 533-MHz DDR2 unbuffered SDRAM   Memory connectors   Memory capacities   Maximum memory   four   128-, 256-, 512-, or 1-GB non-ECC   4 GB   available to the operating system.   BIOS address   F0000h   Computer Information   Chipset   Intel 925X Express or Intel 925XE Express   DMA channels   Interrupt levels   BIOS chip (NVRAM)   NIC   eight   24   4-Mb   Integrated network interface capable of 10/100/1000   communication.   System clock   800- or 1066-MHz data rate (depending on your   processor)   Video   Type   PCI Express   Audio   Type   ADI 1980 AC'97 Codec   NOTE: This audio type is present only on computers   with integrated sound capabilities.   Expansion Bus   Bus type   PCI 2.3   PCI Express x1 and x16   Bus speed   PCI: 33 MHz   PCI Express:   x1 slot bidirectional speed — 500 MB/s   x16 slot bidirectional speed — 8 GB/s   PCI   connector   three   connector size   120 pins   32 bits   connector data width (maximum)   PCI Express   connector   one x1   connector size   36 pins   connector data width (maximum)   1 PCI Express lane   PCI Express   connectors   one x16   connector size   164 pins   connector data width (maximum)   16 PCI Express lanes   Drives   Externally accessible:   two 3.5-inch drive bays   two 5.25-inch drive bays   Available devices   Serial ATA drive, floppy drive, Zip drive, USB memory   devices, CD drive, CD-RW drive, DVD drive, DVD-RW   drive, and DVD and CD-RW combo drive   Internally accessible:   two bays for 1-inch high hard drives   Connectors   External connectors:   Serial   9-pin connector; 16550C-compatible   25-hole connector (bidirectional)   15-hole connector   Parallel   Video   Network adapter   RJ45 connector   PS/2 (keyboard and mouse)   two 6-pin mini-DIN connectors   USB   two front-panel and six back-panel USB 2.0–   compliant connectors   Audio   five connectors for line-in, line-out, microphone,   surround, and center/Low Frequency Effects (LFE)   channel; one front-panel connector for headphones   System board connectors:   Primary IDE drive   Serial ATA   40-pin connector on PCI local bus   four 7-pin connectors   34-pin connector   Floppy drive   Fan   two 5-pin connectors   120-pin connector   PCI 2.3   PCI Express x1   PCI Express x16   Telephony (TAPI)   36-pin connector   164-pin connector   4-pin connector   Controls and Lights   Power control   Power light   push button   green light — Blinking green in sleep state; solid   green for power-on state.   amber light — Blinking amber indicates a problem   with an installed device; solid amber indicates an   Hard-drive access light   green   Link integrity light (on integrated network adapter)   green light — A good connection exists between a   10-Mbps network and the computer.   orange light — A good connection exists between a   100-Mbps network and the computer.   yellow light — A good connection exists between a 1   Gb (or 1000-Mbps) network and the computer.   off (no light) — The computer is not detecting a   physical connection to the network.   Activity light (on integrated network adapter)   Diagnostic lights   yellow blinking light   Standby power light   AUX_PWR on the system board   Power   DC power supply:   Wattage   350 W   Heat dissipation   460.7 BTU/hr   Voltage (see the safety instructions located in   the Product Information Guide for important   voltage setting information)   fixed-voltage power supply — 110 V at 50/60 Hz   manual selection and auto-sensing power supplies —   90 to 135 V at 50/60 Hz; 180 to 265 V at 50/60 Hz;   100 V at 50/60 Hz for Japanese computers   Backup battery   3-V CR2032 lithium coin cell   Physical   Height   Width   42.5 cm (16.7 inches)   18.1 cm (7.1 inches)   44.7 cm (17.6 inches)   12.7 kg (28 lb)   Depth   Weight   Environmental   Temperature:   Operating   10° to 35°C (50° to 95°F)   NOTE: At 35°C (95°F), the maximum operating   altitude is 914 m (3000 ft).   Storage   Relative humidity   Maximum vibration:   Operating   –40° to 65°C (–40° to 149°F)   20% to 80% (noncondensing)   0.25 G at 3 to 200 Hz at 0.5 octave/min   0.5 G at 3 to 200 Hz at 1 octave/min   Storage   Maximum shock:   Operating   bottom half-sine pulse with a change in velocity of 20   inches/sec (50.8 cm/sec)   Storage   27-G faired square wave with a velocity change of   200 inches/sec (508 cm/sec)   Altitude:   Operating   Storage   –15.2 to 3048 m (–50 to 10,000 ft)   –15.2 to 10,668 m (–50 to 35,000 ft)   System Setup   Dell™ Dimension™ 8400 Service Manual   Overview   Use system setup as follows:   l l l To change the system configuration information after you add, change, or remove any hardware in your computer   To set or change a user-selectable option such as the user password   To read the current amount of memory or set the type of hard drive installed   Before you use system setup, it is recommended that you write down the system setup screen information for future reference.   NOTICE: Unless you are an expert computer user, do not change the settings for this program. Certain changes can make your computer work   incorrectly.   Entering System Setup   1. Turn on (or restart) your computer.   2. When the blue DELL™ logo appears, press <F2> immediately.   3. If you wait too long and the operating system logo appears, continue to wait until you see the Microsoft® Windows® desktop. Turn off your computer.   and try again.   System Setup Screens   The system setup screen displays current or changeable configuration information for your computer. Information on the screen is divided into three areas: the   options list, active options field, and key functions.   Option Field — This field contains information about each   option. In this field you can view your current settings and   make changes to your settings.   Options List — This field appears on the left side of the system setup window. The field is a   scrollable list containing features that define the configuration of your computer, including   installed hardware, power conservation, and security features.   Use the right and left arrow keys to highlight an option.   Press <Enter> to make that selection active.   Scroll up and down the list with the up- and down-arrow keys. As an option is highlighted, the   Option Field displays more information about that option and the option's current and   available settings.   Key Functions — This field appears below the Option Field   and lists keys and their functions within the active system   setup field.   System Setup Options   NOTE: Depending on your computer and installed devices, the items listed in this section may not appear, or may not appear exactly as listed.   System   Identifies whether the computer's processor supports Hyper-Threading and lists the processor bus speed, processor ID, clock speed, and   L2 cache.   CPU Info   Memory Info   Indicates amount of installed memory, memory speed, channel mode (dual or single), and type of memory installed.   Date/Time   Displays current date and time settings.   The computer attempts to boot from the sequence of devices specified in this list.   Boot Sequence   NOTE: If you insert a boot device and restart the computer, this option appears in the system setup menu. To boot from a USB memory   device, select the USB device and move it so it becomes the first device in the list.   Drives   Diskette Drive   Identifies and defines the floppy drive attached to the FLOPPY connector on the system board as Off, USB, Internal, or Read Only.   Drives 0   through 5   Identifies the drives attached to the SATA or PRI IDE connectors on the system board, and lists the capacity for hard drives.   Drive   Identifies and defines the SATA controller settings for RAID. You can set the SATA controller to RAID Autodetect/AHCI, RAID   Controller   Autodetect/ATA, or RAID On.   Onboard Devices   You can set the NIC to On (default), Off, or On w/ PXE. When the On w/ PXE setting is active (available only for the future boot   process), the computer prompts the user to press <Ctrl><Alt><b>. Pressing this key combination causes a menu to display that allows   you to select a method for booting from a network server. If a boot routine is not available from the network server, the computer   attempts to boot from the next device in the boot sequence list.   NIC Controller   Audio   Controller   Enables or disables the onboard audio controller.   USB   Set to On (default) so that USB devices will be detected and supported in the operating system.   Enables or disables the onboard PS/2-compatible mouse controller.   Mouse Port   LPT Port Mode   Identifies and defines the parallel port settings. You can set the parallel port to Off, AT, PS/2, EPP, or ECP.   LPT Port   Address   Identifies the address for the parallel port.   LPT Port DMA   Identifies and defines the parallel port DMA settings. You can set the parallel port DMA to Off, DMA1, or DMA3.   Identifies and defines the serial port settings. Auto, the default setting, automatically configures a connector to a particular designation   (COM1 or COM3).   Serial Port #1   Video   Primary Video   Performance   HyperThreading   This setting specifies which video controller is primary when two video controllers are present on the computer.   If your computer's processor supports Hyper-Threading, this option appears in the Options List.   l l l l Bypass — Your computer does not test or change the current acoustics mode setting.   Quiet (default) — The hard drive operates at its most quiet setting.   Suggested — The hard drive operates at the level suggested by the drive manufacturer.   Performance — The hard drive operates at its maximum speed.   Performance   NOTE: Switching to performance mode may cause the drive to be noisier, but its performance is not affected.   NOTE: Changing the acoustics setting does not alter your hard drive image.   Security   This section displays available system security options.   This option provides restricted access to the computer's system setup program in the same way that access to the system can be   restricted with the System Password option.   Admin Password   System Password   Password Status   Displays the current status of the system's password security feature and allows a new system password to be assigned and verified.   This option locks the system password field with the setup password. When the field is locked, you can no longer disable password   security by pressing <Ctrl><Enter> when the computer starts.   Power Management   AC Recovery   Determines what happens when AC power is restored to the computer.   Sets the computer to automatically turn on. Choices are every day or every Monday through Friday.   Auto Power On   The default setting is Off.   This feature does not work if you turn off your computer using a power strip or surge protector.   Sets time to automatically turn on the computer.   Time is kept in a 24-hour format (hours:minutes). Change the start-up time by pressing the right- or left-arrow key to increase or decrease   the numbers, or type numbers in both the date and time fields.   Auto Power Time   Low Power Mode   This feature does not work if you turn off your computer using a power strip or surge protector.   When Low Power Mode is selected, remote wakeup events no longer power up from Hibernate or Off.   This option allows the computer to power up when a NIC or Remote Wakeup-capable modem receives a wake up signal.   On is the default setting. On w/ Boot to NIC allows the computer to attempt to boot from a network prior to using the boot sequence.   Remote Wake Up   NOTE: Normally, the system can be powered up remotely from suspend mode, hibernate mode, or when powered off. When Low Power   Mode (in the Power Management menu) is enabled, the computer can only be powered up remotely from Suspend.   The options are S1, a suspend state where the computer is running in a low-power mode, and S3, a standby state where the power is   reduced or turned off for most components, however, system memory remains active.   Suspend Mode   Maintenance   CMOS Defaults   This setting restores the computer's factory-installed default settings.   Event Log   Displays the system event log.   After downloading a new version of the BIOS, use this option to identify and define the location of the BIOS update file. The options are   Diskette or Disk.   BIOS Update   POST Behavior   Fastboot   When set to On (default), your computer starts more quickly because it skips certain configurations and tests.   This option involves the rightmost bank of keys on your keyboard. When set to On (default), this option activates the numeric and   mathematical features shown at the top of each key. When set to Off, this option activates the cursor-control functions labeled on the   bottom of each key.   Numlock Key   OS Install   This setting turns the OS Install Mode either On or Off (default).   POST Hotkeys   Keyboard Errors   This option allows you to specify the function keys to display on the screen when the computer starts.   This option disables or enables keyboard error reporting when the computer starts.   Boot Sequence   This feature allows you to change the boot sequence for devices.   Option Settings   l l l l Diskette Drive — The computer attempts to boot from the floppy drive. If the floppy disk in the drive is not bootable, if no floppy disk is in the drive, or if   there is no floppy drive installed in the computer, the computer generates an error message.   Hard Drive — The computer attempts to boot from the primary hard drive. If no operating system is on the drive, the computer generates an error   message.   CD Drive — The computer attempts to boot from the CD drive. If no CD is in the drive, or if the CD has no operating system, the computer generates an   error message.   USB Flash Device — Insert the memory device into a USB port and restart the computer. When F12 = Boot Menu appears in the upper-right corner of   the screen, press <F12>. The BIOS detects the device and adds the USB flash option to the boot menu.   NOTE: To boot to a USB device, the device must be bootable. To make sure that your device is bootable, check the device documentation.   Changing Boot Sequence for the Current Boot   You can use this feature, for example, to tell the computer to restart your computer to a USB device such as a floppy drive, memory key, or CD-RW drive.   NOTE: If you are booting to a USB floppy drive, you must first set the floppy drive to OFF in system setup.   1. If you are booting to a USB device, connect the USB device to a USB connector.   2. Turn on (or restart) your computer.   3. When F2 = Setup, F12 = Boot Menu appears in the upper-right corner of the screen, press <F12>.   If you wait too long and the operating system logo appears, continue to wait until you see the Microsoft Windows desktop. Then shut down your   The Boot Device Menu appears, listing all available boot devices. Each device has a number next to it.   4. At the bottom of the menu, enter the number of the device that is to be used for the current boot only.   For example, if you are booting to a USB memory key, highlight USB Flash Device and press <Enter>.   NOTE: To boot to a USB device, the device must be bootable. To make sure your device is bootable, check the device documentation.   Changing Boot Sequence for Future Boots   2. Use the arrow keys to highlight the Boot Sequence menu option and press <Enter> to access the menu.   NOTE: Write down your current boot sequence in case you want to restore it.   3. Press the up- and down-arrow keys to move through the list of devices.   4. Press the spacebar to enable or disable a device (enabled devices have a checkmark).   5. Press plus (+) or minus (–) to move a selected device up or down the list.   Clearing Forgotten Passwords   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   2. Locate the 3-pin password jumper (PASS) on the system board, and attach the jumper plug to pins 2 and 3 to clear the password.   NOTE: When you receive your computer, the jumper plug is attached to pins 1 and 2.   4. Connect your computer and monitor to electrical outlets, and turn them on.   6. Turn off the monitor and disconnect it from the electrical outlet.   7. Disconnect the computer power cable from the electrical outlet, and press the power button to ground the system board.   9. Locate the 3-pin password jumper (PASS) on the system board and attach the jumper to pins 1 and 2 to re-enable the password feature.   NOTICE: To connect a network cable, first plug the cable into the network device and then plug it into the computer.   11. Connect your computer and devices to electrical outlets, and turn them on.   Clearing CMOS Settings   CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide.   2. Reset the current CMOS settings:   b. Remove the jumper plug from pins 2 and 3.   c. Place the jumper plug on pins 1 and 2 and wait approximately 5 seconds.   d. Replace the jumper plug on pins 2 and 3.   NOTICE: To connect a network cable, first plug the cable into the network wall jack and then plug it into the computer.   4. Connect your computer and devices to electrical outlets, and turn them on.   Pin Number   Signal name   +3.3 VDC   +3.3 VDC   COM   Color   Orange   Orange   Black   Red   Wire Gauge   16-AWG   16-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   16-AWG   16-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   18-AWG   1 2 3 4 +5 VDC   COM   5 Black   Red   6 +5 BDC   COM   7 Black   Gray   8 POK   9 +5 VFP   +12 VB DC   +12VB DC   +3.3 VDC   +3.3 VDC   -12 VDC   COM   Purple   White   White   Orange   Orange   Blue   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   Black   Green   Black   Black   Black   N/C   PS-ON   COM   COM   COM   N/C   +5 VDC   +5 VDC   +5 VDC   COM   Red   Red   Red   Black   DC Power Connector P2   Pin Number   Signal Name   COM   18-AWG Wire   1 2 3 4 Black   COM   Black   +12 VA DC   +12 VA DC   Yellow   Yellow   DC Power Connectors, P3 and P5   Pin Number   Signal Name   18-AWG Wire   1 +3.3 VDC   Orange   2 3 4 5 COM   Black   Red   +5 VDC   COM   Black   White   +12 VB DC   DC Power Connector P4   Pin Number   Signal Name   N/C   18-AWG Wire   N/C   1 2 3 4 5 6 COM   Black   COM   Black   +3.3 VDC   +5 VDC   +12B VDC   Orange   Red   White   DC Power Connector P6   Pin Number   Signal Name   +12 VB DC   COM   18-AWG Wire   Yellow   1 2 3 4 Black   COM   Black   +5V DC   Red   DC Power Connector P7   Pin Number   Signal Name   +5 VDC   COM   18-AWG Wire   Red   1 2 3 4 Black   COM   Black   +12 A VDC   Yellow   DC Power Connectors, P8 and P9   Pin Number   Signal Name   18-AWG Wire   1 2 3 4 +12 VB DC   COM   White   Black   Black   Red   COM   +5V DC   DC Power Connector P10   Pin Number   Signal Name   +12 B VDC   +12 B VDC   +12 B VDC   COM   18-AWG Wire   White   1 2 3 4 5 6 White   White   Black   COM   Black   COM   Black   NOTE: The P10 connector is intended for use with PCI Express graphics cards that have power requirements exceeding 75 watts.   Dell™ Dimension™ 8400 Systems Service Manual   Notes, Notices, and Cautions   NOTE: A NOTE indicates important information that helps you make better use of your computer.   NOTICE: A NOTICE indicates either potential damage to hardware or loss of data and tells you how to avoid the problem.   CAUTION: A CAUTION indicates a potential for property damage, personal injury, or death.   Abbreviations and Acronyms   For a complete list of abbreviations and acronyms, see the Dell Dimension Owner's Manual.   If you purchased a Dell™ n Series computer, any references in this document to Microsoft® Windows® operating systems are not applicable.   Information in this document is subject to change without notice.   © 2004 Dell Inc. All rights reserved.   Reproduction in any manner whatsoever without the written permission of Dell Inc. is strictly forbidden.   Trademarks used in this text: Dell, the DELL logo, Inspiron, Dell Precision, Dimension, OptiPlex, Latitude, PowerEdge, PowerVault, PowerApp, and Dell OpenManage are trademarks of Dell   Inc.; Intel and Pentium are registered trademarks of Intel Corporation; Microsoft, Windows, and MS-DOS are registered trademarks of Microsoft Corporation.   Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell Inc. disclaims any   proprietary interest in trademarks and trade names other than its own.   Model DHM   October 2004   Rev. A00   |