Anything could have caused this, instinct tells me a driver issue, have you
recently installed new hardware? Check drivers are upto date particularly
graphics and audio. Could be software, did you load something new recently?
Boot up in safe mode and disable everything in your startup list. Normal
Reboot and test out your system. If all is well keep adding your start up
items one at a time then rebooting until you find one thats causing problems.

That's a start unless you can say what you were doing before the problem
began.

here is more info
and that error
code:

http://search.microsoft.com/results.aspx?form=MSHOME&setlang=en-us&q=0X0000008E&
mkt=en-us