Dell™ Dimension™ 8400 Service Manual Before You Begin Opening the Computer Cover Technical Overview Specifications Advanced Troubleshooting System Setup Removing and Installing Parts Closing the Computer Cover 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.
Back to Contents Page Advanced Troubleshooting Dell™ Dimension™ 8400 Service Manual Power Lights Diagnostic Lights Beep Codes System Messages Power Lights CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
Memory modules are detected, but a memory failure has occurred. l l l A possible graphics card failure has occurred. l l l If you have two or more memory modules installed, remove the modules, reinstall one module, 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.
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 fa
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 correctly in the system setup program. Check the interface cable at both ends. DMA Error Error in the DMA controller on the system board. The keyboard or system board may need to be replaced.
Back to Contents Page Before You Begin Dell™ Dimension™ 8400 Service Manual Getting Started Recommended Tools Turning Off Your Computer Before Working Inside Your Computer 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 You have performed the steps in "Turning Off Your Computer" and "Before Working Inside Your 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. 4. Open the computer cover.
Back to Contents Page 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. 1. Follow the procedures in "Before You Begin." NOTICE: Ensure that sufficient space exists to support the open cover—at least 30 cm (1 ft) of desk top space.
Back to Contents Page 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.
Back to Contents Page Removing and Installing Parts Dell™ Dimension™ 8400 Service Manual Memory Cards Drives Hard Drive Front-Panel Inserts Floppy Drive CD/DVD Drive Airflow Shroud Processor System Board Power Supply Battery 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".
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.
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. 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.
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. If you are installing or replacing a PCI Express card, see "Installing a PCI Express Card." Installing a PCI Card 1. Follow the procedures in "Before You Begin." 2. Press the lever on the card retention arm and raise the retention arm. 3.
7. 8. Before you lower the retention arm, ensure that: l The tops of all cards and filler brackets are flush with the alignment bar. l The notch in the top of the card or filler bracket fits around the alignment guide. 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.
Removing a PCI Card 1. Follow the procedures in "Before You Begin." 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.
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.
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: 10. l The tops of all cards and filler brackets are flush with the alignment bar. l The notch in the top of the card or filler bracket fits around the alignment guide. Press the retention arm into place, securing the card(s) in the computer. NOTICE: Do not route card cables over or behind the cards.
b. 16. 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. Install any drivers required for the card as described in the card documentation. Removing a PCI Express Card 1. Follow the procedures in "Before You Begin." 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.
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.
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.
6. Check all connectors to be certain that they are properly cabled and firmly seated. 7. 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. 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.
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. 8. Connect the data cable to the drive and to the system board.
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.
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.
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. 9. 10. Enter system setup and select the appropriate Diskette Drive option. Verify that your computer works correctly by running the Dell Diagnostics.
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.
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. 1. Follow the procedures in "Before You Begin." 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.
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.
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.
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.
2. Open the computer cover. 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.
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.
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.
Back to Contents Page Specifications Dell™ Dimension™ 8400 Service Manual Processor Processor type Intel® Pentium® 4 with HT Technology NOTE: Not all Pentium 4 processors support HyperThreading technology.
x16 slot bidirectional speed — 8 GB/s PCI connector three connector size 120 pins connector data width (maximum) 32 bits 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.
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) yellow blinking light Diagnostic lights four lights on the back panel (See "Diagnostic Lights.
Back to Contents Page System Setup Dell™ Dimension™ 8400 Service Manual Overview Entering System Setup System Setup Screens System Setup Options Boot Sequence Clearing Forgotten Passwords Clearing CMOS Settings Overview Use system setup as follows: l To change the system configuration information after you add, change, or remove any hardware in your computer l To set or change a user-selectable option such as the user password l To read the current amount of memory or set the type of hard drive insta
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.
Event Log Displays the system event log. BIOS Update 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. POST Behavior Fastboot When set to On (default), your computer starts more quickly because it skips certain configurations and tests. Numlock Key This option involves the rightmost bank of keys on your keyboard.
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. 1. Follow the procedures in "Before You Begin." 2.
3. a. Locate the 3-pin CMOS jumper (CLR CMOS) on the system board. 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. Close the computer cover. 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.
Back to Contents Page Technical Overview Dell™ Dimension™ 8400 Service Manual Inside Your Computer System Board Components Power Supply DC Connector Pin Assignments Inside Your Computer CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide. Follow the procedures in "Before You Begin.
Power Supply DC Connector Pin Assignments DC Power Connector P1
Pin Number Signal name Color Wire Gauge 1 +3.3 VDC Orange 16-AWG 2 +3.3 VDC Orange 16-AWG 3 COM Black 18-AWG 4 +5 VDC Red 18-AWG 5 COM Black 18-AWG 6 +5 BDC Red 18-AWG 7 COM Black 18-AWG 8 POK Gray 18-AWG 9 +5 VFP Purple 18-AWG 10 +12 VB DC White 18-AWG 11 +12VB DC White 18-AWG 12 +3.3 VDC Orange 16-AWG 13 +3.
2 COM Black 3 +5 VDC Red 4 COM Black 5 +12 VB DC White DC Power Connector P4 Pin Number Signal Name 18-AWG Wire 1 N/C N/C 2 COM Black 3 COM Black 4 +3.
1 +12 VB DC White 2 COM Black 3 COM Black 4 +5V DC Red DC Power Connector P10 Pin Number Signal Name 18-AWG Wire 1 +12 B VDC White 2 +12 B VDC White 3 +12 B VDC White 4 COM Black 5 COM Black 6 COM Black NOTE: The P10 connector is intended for use with PCI Express graphics cards that have power requirements exceeding 75 watts.
Back to Contents Page 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.