
dx7400 Illustrated Parts & Service Map, MT Chassis 459782-001 page4
Failsafe Boot Block ROM
The computer comes with a reprogrammable flash system ROM (read only memory). To
upgrade the ROM, download the latest ROM BIOS image from the HP Web site (www.hp.com)
and follow the online GUI/instructions.
Your system ROM includes a Failsafe Boot Block that is protected during the flash process and
allows the computer to be restarted in the unlikely event of an unsuccessful ROM flash.
If the system detects an invalid system ROM during the boot sequence, the Failsafe Boot Block
attempts to locate a valid BIOS image on removable media. To recover from the Boot Block
recovery mode complete the following steps:
Boot Block Recovery
1. Remove any bootable media from the computer and turn off power.
2. Insert a flash drive or CD containing the ROM BIOS.
3. Turn on power to the system.
4. The system will automatically flash the ROM. After a successful flash, the system will either
automatically restart or prompt the user to unplug the unit, wait 5 seconds, reattach the power
cord, and then press the power button.
Password Security
Establishing a Supervisor Password:
1. Turn on or restart the computer. If you are in Windows, click Start > Shut Down > Restart.
2. As soon as the computer is turned on, press F10 when the monitor light turns green to enter
Computer Setup. Press Enter to bypass the title screen, if necessary. If you do not press F10
when prompted, a restart will be necessary.
3. Select Boot > Setup Supervisor Password and follow the instructions on the screen.
4. Before exiting, click File > Save and Exit Setup.
Establishing a User Password:
1. Turn on or restart the computer. If you are in Windows, click Start > Shut Down > Restart.
2. As soon as the computer is turned on, press F10 when the monitor light turns green to enter
Computer Setup. Press Enter to bypass the title screen, if necessary. If you do not press F10
when prompted, a restart will be necessary.
3. Select Boot > Set User Password and follow the instructions on the screen.
Before exiting, click File > Save and Exit Setup.
Changing a Password:
1. Turn on or restart the computer. If you are in Windows, click Start> Shut Down > Restart.
2. As soon as the computer is turned on, press F10 when the monitor light turns green to enter
Computer Setup.
3. When the key icon appears, type your current password
4. Select Boot > Set Supervisor (or user) Password.
5. Enter the new password (or nothing for no password) in the key icon and press Enter
The new password will take effect the next time the computer is restarted.
Deleting a Password
1. Turn on or restart the computer. If you are in Windows, click Start > Shut Down > Restart.
2. As soon as the computer is turned on, press F10 when the monitor light turns green to enter
Computer Setup.
3. When the key icon appears, type your current password
4. Select Boot > Set Supervisor (or user) Password.
5. Enter nothing for no password in the key icon and press Enter.
The new password will take effect the next time the computer is restarted.
Clearing CMOS
1. Turn off the computer and any external devices, disconnect the power cord from the power
outlet, and remove the access panel.
2. Locate, press, and hold the CMOS button in for five seconds.
3. Replace the access panel and connect the power cord to the power outlet.
4. Turn on the computer.
Error Conditions and Messages
Diagnostic Functions
Diagnostic functions are provided by the Setup Utility (in system ROM) and by Insight Diag-
nostics. Insight Diagnostics provides detailed system information including:
• Processor type and speed
• Memory amount, mapping, and integrity
• Hardware peripheral availability/settings
• Hard drive type, space used/available
• System identification, asset tracking
Insight Diagnostics may be found on the Documentation and Diagnostics CD that shipped with
the computer. The tool may also be downloaded from the hp Web site using the following pro-
cedure:
1. Go to www.hp.com
2. Click the Software and Download driver link.
3. Enter the product number (for example, dx7400) in the text box and press the Enter key.
4. Select the specific product.
5. Select the OS.
6. Click the Diagnostics link.
7. Select HP Insight Diagnostics Offline Edition.
8. Select the proper language and click Download.
Feature Purpose
How It Is
Established
Floppy drive controller Prevents the transfer of data to or from the
floppy drive.
Setup Utilities
Device Boot Disabling Prevents booting from and or all of these
devices: Internal or external USB, Internal
ODD, or Internal FDD
Setup Utilities
Security Option Prevents use of computer until password is
entered. Can apply to both initial startup and
restart.
Setup Utilities
BIOS Write Protect Restricts ability to change ROM BIOS with-
out approval.
Setup Utilities
USB Controller Allows you to disable or enable all USB
devices.
Setup Utilities
Common POST Error Messages
Screen Message Probable Cause Recommended Action
101-Option ROM Check-
sum Error
1. System ROM checksum
error.
2. Expansion board option
ROM checksum
3. System board
1. Verify ROM, reflash if required
2. Remove suspected card, reboot
3. Clear CMOS memory, reboot
4. Replace system board
103-System Board
Failure
DMA, timers 1. Clear CMOS memory.
2. Remove expansion boards.
3. Replace system board.
164-Memory Size Error
and
201-Memory Error
Incorrect memory configu-
ration
1. Run Setup (F10).
2. Check DIMMs for proper
seating, type, and HP
compatibility.
3. Remove DIMMs singularly and
reboot to isolate faulty DIMM.
4. Replace system board.
214-DIMM Configura-
tion Warning
Populated DIMM configura-
tion is not optimized
Rearrange the DIMMs so that
each channel has the same amount
of memory.
301-, 304-Keyboard error Keyboard failure. Check keyboard connection or
keys. Check connector for bent of
missing pins. Replace keyboard. If
304, possible system board prob-
lem.
501-Display Adapter
Failure
Graphics display controller. 1. Reseat graphics card.
2. Clear CMOS.
3. Check monitor connection.
4. Replace graphics card.
1720-SMART Hard Drive
Detects Imminent Failure
Hard drive is about to fail. 1. Determine if hard drive is
giving correct error message.
Enter Computer Setup and run
the Drive Protection System
test under Storage > DPS Self-
test.
2. Apply hard drive firmware
patch if applicable.
3. Back up contents and replace
hard drive.
1796-SATA Cabling Error One or more SATA devices
are improperly attached. For
optimal performance, the
SATA 0 and SATA 1 con-
nectors must be used before
SATA 2 and SATA 3.
Ensure SATA connectors are used
in ascending order. For one
device, use SATA 0. For two
devices, use SATA 0 and SATA 1.
For three devices, use SATA 0,
SATA1, and SATA 2.
1801-Microcode Patch
Error
Processor not supported by
ROM BIOS.
1. Upgrade BIOS to proper
version.
2. Change the processor.
Diagnostic LEDs
LED Color LED Activity State/Message
Power Green On Computer on
Power Green 1 blink every second Processor thermal protection activated,
fan blocked or not turning, OR
Fansink not properly attached
Power Green 2 blinks every second Suspend to RAM (some Models)
Power Green 5 blinks, 1 blink every second
followed by 1 short beep
Pre-video memory error
Power Green 6 blinks, 1 blink every second
followed by a 1 long and 2
short beeps
Pre-video graphics error
Power Green 8 blinks, 1 blink every second
followed by 2 short beeps
Invalid ROM with diskette drive
Power Green 8 blinks, 1 blink every second
followed by 2 short beeps and
hurried beeps
Invalid ROM without diskette drive
None None System does not power on and
LEDs are not flashing
System unable to power on