problem while playing games

[stealthbike]

Well, I wasnt sure where to post this, but since it happen only when i play games, I posted here.
Here's my problem:
WHen i play any games, after a while i get this:
DRIVER_IRQL_NOT_LESS_OR_EQUAL
0x100000d1 (0xba8b2037, 0x00000002, 0x00000000, 0xf813ec5c).

Here's my spec:
Intel P4 3,0 Ghz
WinXP with sp2
Intel MotherBoard 865 GBFL
Western Digital 160Gig hard drive
RADEON 9200 128 Mb
Intel(R) PRO/100 VE Network Connection
AC 97 Soundcard
DDR-400 512Mb RAM Crucial/Kingston

I had this problem before installing sp2.
I updated the videocard driver, but all it did was making it happen less often.
I also tested the Ram with memtest86 for 2 hours without any error.

Any help would be appreciated.

[Force Flow]

DDR-400 512Mb RAM Crucial/Kingston

So, which do you have? Crucial or Kingston? Or is it a mix of both brands? If so, you will probably have to drop the RAM bus down to 333.