Restart itself [DUMP DATA]

For some reason my windows XP machine restart itself, I can only see a bugcheck in the event viewer 0x1000008e error, my minidump file shown below, and it always gives exactly same error each restart. Could any one tell me what went wrong either hardware or software? Many thanks!
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Loading Dump File [G:\Download\Minidump\Mini071405-01.dmp]
Mini Kernel Dump File: Only registers and stack trace are available

Symbol search path is: SRV*G:\Download\Minidump*http://msdl.microsoft.com/download/symbols
Executable search path is:
Windows XP Kernel Version 2600 (Service Pack 2) MP (2 procs) Free x86 compatible
Product: WinNt, suite: TerminalServer SingleUserTS
Built by: 2600.xpsp_sp2_gdr.050301-1519
Kernel base = 0x804d7000 PsLoadedModuleList = 0x805624a0
Debug session time: Thu Jul 14 14:23:04.107 2005 (GMT+10)
System Uptime: 1 days 1:20:17.541
Loading Kernel Symbols
.................................................................................................................

..............
Loading unloaded module list
......................................
Loading User Symbols
*******************************************************************************
* *
* Bugcheck Analysis *
* *
*******************************************************************************

Use !analyze -v to get detailed debugging information.

BugCheck 1000008E, {c0000005, bf804915, a7b50b48, 0}

Probably caused by : win32k.sys ( win32k!GreDCSelectBrush+86 )

Followup: MachineOwner
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0: kd> !analyze -v
*******************************************************************************
* *
* Bugcheck Analysis *
* *
*******************************************************************************

KERNEL_MODE_EXCEPTION_NOT_HANDLED_M (1000008e)
This is a very common bugcheck. Usually the exception address pinpoints
the driver/function that caused the problem. Always note this address
as well as the link date of the driver/image that contains this address.
Some common problems are exception code 0x80000003. This means a hard
coded breakpoint or assertion was hit, but this system was booted
/NODEBUG. This is not supposed to happen as developers should never have
hardcoded breakpoints in retail code, but ...
If this happens, make sure a debugger gets connected, and the
system is booted /DEBUG. This will let us see why this breakpoint is
happening.
Arguments:
Arg1: c0000005, The exception code that was not handled
Arg2: bf804915, The address that the exception occurred at
Arg3: a7b50b48, Trap Frame
Arg4: 00000000

Debugging Details:
------------------


EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at "0x%08lx" referenced memory at "0x%08lx ". The memory

could not be "%s ".

FAULTING_IP:
win32k!GreDCSelectBrush+86
bf804915 f60704 test byte ptr [edi],0x4

TRAP_FRAME: a7b50b48 -- (.trap ffffffffa7b50b48)
ErrCode = 00000000
eax=e3b36fb0 ebx=e3b36f88 ecx=e2ccac90 edx=85898ddc esi=e61ce008 edi=006e0fc0
eip=bf804915 esp=a7b50bbc ebp=a7b50bcc iopl=0 nv up ei pl nz na pe cy
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00010203
win32k!GreDCSelectBrush+0x86:
bf804915 f60704 test byte ptr [edi],0x4 ds:0023:006e0fc0=??
Resetting default scope

CUSTOMER_CRASH_COUNT: 1

DEFAULT_BUCKET_ID: INTEL_CPU_MICROCODE_ZERO

BUGCHECK_STR: 0x8E

LAST_CONTROL_TRANSFER: from bf806138 to bf804915

STACK_TEXT:
a7b50bcc bf806138 e61ce008 01100081 00000000 win32k!GreDCSelectBrush+0x86
a7b50c00 bf80c437 010102ef 00000001 e61ce008 win32k!XDCOBJ::bCleanDC+0x25
a7b50c14 bf8c1de5 010102ef 00000001 00000001 win32k!bDeleteDCInternal+0x26
a7b50c2c bf8c1ca9 00001404 e61d8008 00000000 win32k!vCleanupDCs+0x28
a7b50c48 bf8c0397 e61d8008 00000000 00000000 win32k!NtGdiCloseProcess+0x1a
a7b50c60 bf820e88 e61d8008 00000000 85898da8 win32k!GdiProcessCallout+0xea
a7b50c7c 8058c2bf 857b1378 00000000 85898da8 win32k!W32pProcessCallout+0x5c
a7b50d08 805739b4 00000000 85898da8 00000000 nt!PspExitThread+0x3e4
a7b50d28 8058c631 85898da8 00000000 a7b50d64 nt!PspTerminateThreadByPointer+0x52
a7b50d54 804dd99f 00000000 00000000 0012fedc nt!NtTerminateProcess+0x118
a7b50d54 7c90eb94 00000000 00000000 0012fedc nt!KiFastCallEntry+0xfc
WARNING: Frame IP not in any known module. Following frames may be wrong.
0012fedc 00000000 00000000 00000000 00000000 0x7c90eb94


FOLLOWUP_IP:
win32k!GreDCSelectBrush+86
bf804915 f60704 test byte ptr [edi],0x4

SYMBOL_STACK_INDEX: 0

FOLLOWUP_NAME: MachineOwner

SYMBOL_NAME: win32k!GreDCSelectBrush+86

MODULE_NAME: win32k

IMAGE_NAME: win32k.sys

DEBUG_FLR_IMAGE_TIMESTAMP: 422511a2

STACK_COMMAND: .trap ffffffffa7b50b48 ; kb

FAILURE_BUCKET_ID: 0x8E_win32k!GreDCSelectBrush+86

BUCKET_ID: 0x8E_win32k!GreDCSelectBrush+86

Followup: MachineOwner

 

The output of your minidump does not have any clues. Does your windows crashes with another bugcheck codes such as 0A, 19, 24, 50 or D1. If yes, attach the analysis report of the minidump that have different bugcheck codes.

 

Event viewer

Basically this is what I got from the event viewer and everytime is the same:

The computer has rebooted from a bugcheck. The bugcheck was: 0x1000008e (0xc0000005, 0xbf804915, 0xa9279b48, 0x00000000). A dump was saved in: C:\WINDOWS\Minidump\Mini071305-01.dmp.