Here is what microsoft says about it.
Stop 0x000000D1 or DRIVER_IRQL_NOT_LESS_OR_EQUAL
The Stop 0xD1 message indicates that the system attempted to access pageable memory using a kernel process IRQL that was too high. Drivers that have used improper addresses typically cause this error.
Interpreting the Message
This Stop message has four parameters:
Memory referenced.
IRQL at time of reference.
Type of access (0x00000000 = read operation, 0x00000001 = write operation).
Address that referenced memory.
Resolving the Problem
For additional troubleshooting suggestions that apply to all Stop errors, see "Stop Message Checklist" later in this appendix.
Stop 0xD1 messages can occur after installing faulty drivers or system services. If a driver is listed by name, disable, remove, or roll back that driver to confirm that this resolves the error. If so, contact the manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, DVD playback, and CD mastering tools.
For more information about Stop 0xD1 messages, see the Microsoft Knowledge Base link on the Web Resources page at
http://www.microsoft.com/windows/reskits/webresources. Search using keywords winnt, 0x000000D1, and 0xD1.
updated and comaptiable drivers are very important when running XP. Check your hardware with the HCL
www.microsoft.com/hcl If you hardware is not on the list it does not mean it won't work it just means it hasn't been tested by Microsoft and they won't Guarantee it to be compatible. If it not on the list check the manufacturer's website fo an up to date XP driver, if they don't have one you may be out of luck. This goes for motherboards and the bios too