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Advanced Troubleshooting

Dell Precision™ Workstations 450 and 650 User's Guide

  Diagnostic Lights

  Beep Codes

  Dell Diagnostics

  Drivers

  Using System Restore

  Resolving Software and Hardware Incompatibilities

Diagnostic Lights

System Lights

Located on the front of the computer, these lights can indicate a computer problem.

Power Light	Hard-Drive Light	Problem Description	Suggested Resolution
Solid green	N/A	Power is on, and the computer is operating normally.	No corrective action is required.
Blinking green	Blank	The computer is in the suspended state (Microsoft® Windows® 2000 and Windows XP).	Press the power button, move the mouse, or press a key on the keyboard to wake the computer. See "Power Button."
Blinks green several times and then turns off	N/A	A configuration error exists.	Check the diagnostic lights to see if the specific problem is identified.
Solid yellow	N/A	The Dell Diagnostics is running a test, or a device on the system board may be faulty or incorrectly installed.	If the Dell Diagnostics is running, allow the testing to complete. Check the diagnostic lights to see if the specific problem is identified. See "System Board Problems." If the computer does not boot, contact Dell for technical assistance.
Blinking yellow	Blank	A power supply or system board failure has occurred.	Check the diagnostic lights to see if the specific problem is identified. See "Power Problems" and "System Board Problems."
Blinking yellow	Solid green	A system board or VRM failure has occurred.	Check the diagnostic lights to see if the specific problem is identified. See "System Board Problems."
Solid green and a beep code during POST	N/A	A problem was detected while the BIOS was executing.	See "Beep Codes" for instructions on diagnosing the beep code. Also, check the diagnostic lights to see if the specific problem is identified.
Solid green power light and no beep code and no video during POST	N/A	The monitor or the graphics card may be faulty or incorrectly installed.	Check the diagnostic lights to see if the specific problem is identified. See "Video and Monitor Problems."
Solid green power light and no beep code but the computer locks up during POST	N/A	An integrated system board device may be faulty.	Check the diagnostic lights to see if the specific problem is identified. If the problem is not identified, contact Dell for technical assistance.

Diagnostic Lights

To help you troubleshoot a problem, your computer is equipped with four lights on the front panel labeled "A," "B," "C," and "D". These lights can be yellow or green. When the computer starts normally, the lights flash. After the computer starts, the lights remain green. If the computer malfunctions, the color and sequence of the lights identify the problem.

CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the System Information Guide.

Diagnostic Light Codes Before POST

Light Pattern	Problem Description	Suggested Resolution
	No electrical power is supplied to the computer.	Connect the computer to its electrical outlet. Ensure that the front-panel power light is on. If the power light is off, ensure that the computer is connected to a working electrical outlet and then press the power button. If the problem is still not resolved, contact Dell for technical assistance.
	The computer is in a normal off condition; the computer is connected to its electrical outlet.	Press the power button to turn the computer on. If the computer does not turn on, ensure that the front-panel power light is on. If the power light is off, ensure that the computer is connected to a working electrical outlet and then press the power button. If the problem is still not resolved, contact Dell for technical assistance.
	The computer is in a reduced power or "sleep" state.	Use one of the appropriate methods to "wake up" the computer. See "Advanced Features." If the problem is not resolved and you are trying to wake the computer with a USB mouse or keyboard, subsitute the mouse or keyboard with a working PS/2 mouse or keyboard and try to wake the computer.
	The BIOS is not executing.	Ensure that the microprocessor is seated correctly and restart the computer. If the problem is still not resolved, contact Dell for technical assistance.
	A possible power supply or power cable failure has occurred.	Perform the procedure in "Power Problems." If the problem is still not resolved, contact Dell for technical assistance.
	A possible system board failure has occured.	Contact Dell for technical assistance.
	A microprocessor and/or VRM mismatch exists.	Perform the procedure in "Microprocessor Problems."
	A possible VRM 0 failure has occurred.	Contact Dell for technical assistance.
	A possible VRM 1 failure has occurred.	Perform the procedure in "Microprocessor Problems."
	A possible VRM 0 and VRM 1 failure has occurred.	Contact Dell for technical assistance.

Diagnostic Light Codes During POST

Light Pattern	Problem Description	Suggested Resolution
	A possible BIOS failure has occurred; the computer is in the recovery mode.	Run the BIOS Recovery Utility, wait for recovery completion, and then restart the computer.
	A possible microprocessor failure has occurred.	Reinstall the microprocessor and restart the computer.
	Memory modules are detected, but a memory failure has occurred.	Reseat the memory modules to ensure that your computer is successfully communicating with the memory. Restart the computer. If the problem still exists, remove all the memory modules and install one memory module in memory module connector 4. Restart the computer. The following message appears: Alert! Operating in Debug Mode. Please Populate Memory in Pairs for Normal Operation. Press <F1> to boot to the operating system. Run the Dell Diagnostics. If the memory module passes, shut down the computer, remove the memory module, and repeat the process with the remaining memory modules until a memory error occurs during start-up or diagnostic testing. If the first memory module tested is defective, repeat the process with the remaining modules to ensure the remaining modules are not defective. When the defective memory module is identified, contact Dell for a replacement. NOTE: If necessary, the computer can operate in debug mode until new memory modules are installed.
	A possible expansion card failure has occurred.	Determine if a conflict exists by removing a card (not the video card) and then restarting the computer. If the problem persists, reinstall the card that you removed, remove a different card, and then restart the computer. Repeat this process for each card. If the computer starts normally, troubleshoot the last card removed from the computer for resource conflicts (see "Resolving Software and Hardware Incompatibilities"). If the problem persists, contact Dell.
	A possible graphics card failure has occurred.	Reinstall the graphics card and restart the computer. If the problem still exists, install a graphics card that you know works and restart the computer. If the problem persists, contact Dell.
	A possible floppy or hard drive failure has occurred.	Check all power and data cable connections, and then 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.	Reseat the memory modules to ensure that your computer is successfully communicating with the memory. Restart the computer. If the problem still exists, remove all the memory modules and install one memory module in memory module connector 4. Restart the computer. The following message appears: Alert! Operating in Debug Mode. Please Populate Memory in Pairs for Normal Operation. Press <F1> to boot to the operating system. Run the Dell Diagnostics. If the memory module passes, shutdown the computer, remove the memory module, and repeat the process with the remaining memory modules until a memory error occurs during start-up or diagnostic testing. If the first memory module tested is defective, repeat the process with the remaining modules to ensure the remaining modules are not defective. When the defective memory module is identified, contact Dell for a replacement. NOTE: If necessary, the computer can operate in debug mode until new memory modules are installed.
	System board failure has occurred.	Perform the procedures in "System Board Problems." If the problem persists, contact Dell.
	Memory modules are detected, but a memory configuration or compatibility error exists.	Ensure that there are no special memory module/memory connector placement requirements (see "Memory"). Verify that the memory modules that you are installing are compatible with your computer (see "Memory"). Reinstall the memory modules and then restart the computer. If the problem persists, contact Dell.
	A possible system board resource and/or hardware failure has occurred.	Perform the procedure in "System Board Problems" and see "Resolving Software and Hardware Incompatibilities." If the problem persists, contact Dell.
	A possible expansion card failure has occurred.	Determine if a conflict exists by removing a card and then restarting the computer. If the problem persists, reinstall the card that you removed, remove a different card, and then restart the computer. Repeat this process for each card. If the computer starts normally, troubleshoot the last card removed from the computer for resource conflicts (see "Resolving Software and Hardware Incompatibilities"). If the problem persists, contact Dell.
	Other failure has occurred.	Ensure that the cables are properly connected from the hard drive, CD drive, and DVD drive to the system board. If the problem persists, contact Dell.
	The computer is in a normal operating condition after POST.	None.

Beep Codes

Your computer might emit a series of beeps that identify a problem. One possible series (code 1-3-1) consists of one beep, a burst of three beeps, and then one beep. This series tells you that the computer encountered a memory problem.

1. Write the beep code down on the Diagnostic Checklist.
   
   
2. Run the Dell Diagnostics to identify a more serious cause.
   
   
3. Contact Dell for 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
1-3	Video Memory Test failure
1-3-1 through 2-4-4	DIMMs not being properly identified or used
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
4-3-1	Memory failure above address 0FFFFh
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
4-4-2	Failure to decompress code to shadowed memory
4-4-3	Math-coprocessor test failure
4-4-4	Cache test failure

Dell Diagnostics

When to Use the Dell Diagnostics

If you experience a problem with your computer, perform the checks in "Solving Problems" and run the Dell Diagnostics before you contact Dell for technical assistance. Running the Dell Diagnostics may help you resolve the problem without contacting Dell. If you do contact Dell, the test results can provide important information for Dell's service and support personnel.

The Dell Diagnostics allows you to:

• Perform express, extended, or custom tests on one or all devices
  
  
• Select tests based on a symptom of the problem you are having
  
  
• Choose how many times a test is run
  
  
• Display test results
  
  
• Suspend testing if an error is detected
  
  
• Access online help information that describes the tests and devices
  
  
• Receive status messages that tell you whether tests completed successfully
  
  
• Receive error messages if problems are detected
  
  

Starting the Dell Diagnostics

It is recommended that you print these procedures before you begin.

NOTICE: Only use the Dell Diagnostics to test your Dell™ computer. Using this program with other computers can result in error messages.

Enter system setup, review your computer's configuration information, and ensure that the device you want to test displays in system setup and is active.

Start the Dell Diagnostics from either your hard drive or from the Drivers and Utilities CD (also known as the ResourceCD).

Starting the Dell Diagnostics From Your Hard Drive

1. Shut down and restart the computer.
   
   
2. When the DELL® logo appears, press <F12> immediately.
   
   

NOTE: If you receive a message stating that no Diagnostics utility partition has been found, follow the instructions to run the Dell Diagnostics from your Drivers and Utilities CD.

If you wait too long and the Microsoft® Windows® logo appears, continue to wait until you see the Windows desktop. Then shut down your computer through the Start menu and try again.

3. When the boot device list appears, highlight Boot to Utility Partition and press <Enter>.
   
   
4. When the Dell Diagnostics Main Menu appears, select the test you want to run.
   
   

Starting the Dell Diagnostics From the Drivers and Utilities CD

1. Insert the Drivers and Utilities CD into the CD drive.
   
   
2. Shut down and restart the computer.
   
   

When the DELL® logo appears, press <F12> immediately.

If you wait too long and the Windows logo appears, continue to wait until you see the Windows desktop. Then shut down your computer through the Start menu and try again.

NOTE: This feature changes the boot sequence for one time only. On the next start-up, the computer boots according to the devices specified in system setup.

3. When the boot device list appears, highlight IDE CD-ROM Device and press <Enter>.
   
   
4. Select the IDE CD-ROM Device option from the CD boot menu.
   
   
5. Select the Boot from CD-ROM option from the menu that appears.
   
   
6. Type 1 to start the ResourceCD menu.
   
   
7. Type 2 to start the Dell Diagnostics.
   
   
8. Select Run the 32 Bit Dell Diagnostics from the numbered list. If multiple versions are listed, select the version appropriate for your platform.
   
   
9. When the Dell Diagnostics Main Menu appears, select the test you want to run.
   
   

Dell Diagnostics Main Menu

1. After the Dell Diagnostics loads and the Main Menu screen appears, click the button for the option you want.
   
   

NOTE: The Service Tag number for your computer is located on the top of each test screen.

Option	Function
Express Test	Performs a quick test of devices. This test typically takes 10 to 20 minutes and requires no interaction on your part. Run Express Test first to increase the possibility of tracing the problem quickly.
Extended Test	Performs a thorough check of devices. This test typically takes an hour or more and requires you to answer questions periodically.
Custom Test	Tests a specific device. You can customize the tests you want to run.
Symptom Tree	Lists the most common symptoms encountered and allows you to select a test based on the symptom of the problem you are having.

2. If a problem is encountered during a test, a message displaying the error code and a description of the problem appear. Write down the error code and problem description and follow the instructions on the screen.
   
   

If you cannot resolve the error condition, contact Dell.

3. If you run a test from the Custom Test or Symptom Tree option, click the applicable tab described in the following table for more information.
   
   

Tab	Function
Results	Displays the results of the test and any error conditions encountered.
Errors	Displays error conditions encountered, error codes, and problem description.
Help	Describes the test and may indicate requirements for running the test.
Configuration	Displays your hardware configuration for the selected device. The Dell Diagnostics obtains your configuration information for all devices from system setup, memory, and various internal tests and displays it in the device list in the left pane of the screen. The device list may not display the names of all the components installed on your computer or all devices attached to your computer.
Parameters	Allows you to customize the test by changing the test settings.

4. When the tests are completed, if you are running the Dell Diagnostics from the Drivers and Utilities CD, remove the CD.
   
   
5. Close the test screen to return to the Main Menu screen. To exit the Dell Diagnostics and restart the computer, close the Main Menu screen.
   
   

Drivers

What Is a Driver?

A driver is a program that controls a device such as a printer, mouse, or keyboard. All devices require a driver program.

A driver acts like a translator between the device and the programs that use the device. Each device has its own set of specialized commands that only its driver recognizes.

Many drivers, such as the keyboard driver, come with your Microsoft^® Windows^® operating system. You may need to install drivers if:

• You upgrade your operating system.
  
  
• You reinstall your operating system.
  
  
• You connect or install a new device.
  
  

If you experience a problem with any device, perform the steps in the following sections to identify whether the driver is the source of your problem and if necessary, to update the driver.

Identifying Drivers

Windows XP

1. Click the Start button and click Control Panel.
   
   
2. In the Control Panel window, under Pick a Category, click Performance and Maintenance.
   
   
3. In the Performance and Maintenance window, click System.
   
   
4. In the System Properties window, click the Hardware tab.
   
   
5. Click Device Manager.
   
   
6. In the Device Manager window, scroll down the list to see if any device has an exclamation point (a yellow circle with a [!]) on the device icon.
   
   

If an exclamation point is next to the device name, you may need to reinstall the driver or install a new driver.

Windows 2000

1. Click the Start button, point to Settings, and click Control Panel.
   
   
2. In the Control Panel window, double-click System.
   
   
3. In the System Properties window, click the Hardware tab.
   
   
4. Click Device Manager.
   
   
5. In the Device Manager window, scroll down the list to see if any device has an exclamation point (a yellow circle with a [!]) on the device icon.
   
   

If an exclamation point is next to the device name, you may need to reinstall the driver or install a new driver.

Reinstalling Drivers

NOTICE: The Dell Support website and your Dell Precision Drivers and Utilities CD provide approved drivers for Dell™ computers. If you install drivers obtained from other sources, your computer might not work correctly.

NOTE: To access device drivers and user documentation, you must use the Drivers and Utilities CD while your computer is running Windows.

1. Insert the Drivers and Utilities CD into the CD drive.
   
   

If this is your first time to use the Drivers and Utilities CD, the Installation window opens to inform you that the CD will begin the installation. Click OK, and respond to the installation program prompts to complete the installation.

2. Click Next at the Welcome Dell System Owner screen.
   
   
3. Choose the appropriate selections for System Model, Operating System, Device Type, and Topic.
   
   
4. Click My Drivers in the Topic drop-down menu.
   
   

The Drivers and Utilities CD scans your computer's hardware and operating system and then displays a list of device drivers for your system configuration.

5. Click the appropriate driver and follow the instructions to download the driver for your computer.
   
   

To view a list of all available drivers for your computer, click Drivers in the Topic drop-down menu.

To access the Dell Drivers and Utilities CD Guide, click User's Guides in the Topic drop-down menu, and then click Dell Precision ResourceCD.

Using Windows XP Device Driver Rollback

If a problem occurs on your computer after you install or update a driver, use Windows XP Device Driver Rollback to replace the driver with the previously installed version.

To use Device Driver Rollback:

1. Click the Start button and click Control Panel.
   
   
2. In the Control Panel window, under Pick a Category, click Performance and Maintenance.
   
   
3. In the Performance and Maintenance window, click System.
   
   
4. In the System Properties window, click the Hardware tab.
   
   
5. Click Device Manager.
   
   
6. In the Device Manager window, right-click the device for which the new driver was installed, and then click Properties.
   
   
7. Click the Drivers tab.
   
   
8. Click Roll Back Driver.
   
   

If Device Driver Rollback does not resolve the problem, then use Using System Restore to return your operating system to the operating state it was in before you installed the new driver.

Using System Restore

The Microsoft^® Windows^® XP operating system provides System Restore to allow you to return your computer to an earlier operating state (without affecting data files) if changes to the hardware, software, or other system settings have left the computer in an undesirable operating state. See Windows Help for information on using System Restore.

NOTICE: Make regular backups of your data files. System Restore does not monitor your data files or recover them.

Creating a Restore Point

1. Click the Start button.
   
   
2. Click Help and Support.
   
   
3. Click System Restore.
   
   
4. Follow the instructions on the screen.
   
   

Restoring the Computer to an Earlier Operating State

If problems occur after installing a device driver, first try using Device Driver Rollback. If that is unsuccessful, then use System Restore.

NOTICE: Before restoring the computer to an earlier operating state, save and close all open files and close all open programs. Do not alter, open, or delete any files or programs until the system restoration is complete.

1. Click the Start button, point to All Programs® Accessories® System Tools, and then click System Restore.
   
   
2. Ensure that Restore my computer to an earlier time is selected, and then click Next.
   
   
3. Click a calendar date to which you want to restore your computer.
   
   

The Select a Restore Point screen provides a calendar that allows you to see and select restore points. All calendar dates with available restore points appear in bold.

4. Select a restore point, and then click Next.
   
   

If a calendar date has only one restore point, then that restore point is automatically selected. If two or more restore points are available, click the restore point that you prefer.

5. Click Next.
   
   

The Restoration Complete screen appears after System Restore finishes collecting data, and then the computer automatically restarts.

6. After the computer restarts, click OK.
   
   

To change the restore point, you can either repeat the steps using a different restore point, or you can undo the restoration.

Undoing the Last System Restore

NOTICE: Before undoing the last system restore, save and close all open files and close all open programs. Do not alter, open, or delete any files or programs until the system restoration is complete.

1. Click the Start button, point to All Programs ®
   Accessories ® System Tools, and then click System Restore.
   
   
2. Select Undo my last restoration and click Next.
   
   
3. Click Next.
   
   

The System Restore screen appears, and then the computer automatically restarts.

4. After the computer restarts, click OK.
   
   

Enabling System Restore

If you reinstall Windows XP with less than 200 MB of free hard-disk space available, System Restore is automatically disabled. To see if System Restore is enabled:

1. Click the Start button, and then click Control Panel.
   
   
2. Click Performance and Maintenance.
   
   
3. Click System.
   
   
4. Click the System Restore tab.
   
   
5. Make sure that Turn off System Restore is unchecked.
   
   

Resolving Software and Hardware Incompatibilities

Windows XP

Microsoft^® Windows^® XP IRQ conflicts occur if a device either is not detected during the operating system setup or is detected but incorrectly configured.

To check for conflicts on a computer running Windows XP:

1. Click the Start button, and then click Control Panel.
   
   
2. Click Performance and Maintenance, and then click System.
   
   
3. Click the Hardware tab, and then click Device Manager.
   
   
4. In the Device Manager list, check for conflicts with the other devices.
   
   

Conflicts are indicated by a yellow exclamation point (!) beside the conflicting device or a red X if the device has been disabled.

5. Double-click any conflicting device listed to bring up the Properties window to determine what needs to be reconfigured or removed from the Device Manager.
   
   

Resolve these conflicts before checking specific devices.

6. Double-click the malfunctioning device type in the Device Manager list.
   
   
7. Double-click the icon for the specific device in the expanded list.
   
   

The Properties window appears.

8. Resolve any IRQ conflicts, as described in step 5.
   
   

If an IRQ conflict exists, the Device status area in the Properties window reports the cards or devices that share the device's IRQ.

To use the Windows XP Hardware Troubleshooter:

1. Click the Start button, and then click Help and Support.
   
   
2. Type hardware troubleshooter in the Search field, and then click the arrow to start the search.
   
   
3. Click Hardware Troubleshooter in the Search Results list.
   
   
4. In the Hardware Troubleshooter list, click I need to resolve a hardware conflict on my computer, and then click Next.
   
   

Windows 2000

To check for conflicts on a computer running Windows 2000:

1. Click the Start button, point to Settings, and click Control Panel.
   
   
2. In the Control Panel window, double-click System.
   
   
3. Click the Hardware tab.
   
   
4. Click Device Manager.
   
   
5. Click View, and then click Resources by connection.
   
   
6. Double-click Interrupt request (IRQ) to view the IRQ assignments.
   
   

Conflicts are indicated by a yellow exclamation point (!) beside the conflicting device or a red X if the device has been disabled.

7. Double-click any conflicting device listed to bring up the Properties window to determine what needs to be reconfigured or removed from the Device Manager. Resolve these conflicts before checking specific devices.
   
   
8. Double-click the malfunctioning device type in the Device Manager list.
   
   
9. Double-click the icon for the specific device in the expanded list.
   
   

The Properties window appears.

10. If an IRQ conflict exists, the Device status area in the Properties window reports the cards or devices that share the device's IRQ. Resolve the IRQ conflicts.
    
    

To use the Windows 2000 Hardware Troubleshooter:

1. Click the Start button, and then click Help.
   
   
2. Click Troubleshooting and Maintenance on the Contents tab, click Windows 2000 troubleshooters, and then click Hardware.
   
   
3. In the Hardware Troubleshooter list, click I need to resolve a hardware conflict on my computer, and then click Next.
   
   

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