Since it says system service I'd guess it's just a software glitch. Any new software? or hardware with drivers installed recently? (or updated)

Does it boot in safe mode? (f8 during startup and you should get a menu prompting startup in safemode (with or without networking doesn't really matter)
If it does it just points to more of a software problem.. then it's hunting it down.

You might also try disconnecting any USB devices that are connected and see if that makes any difference.

A quick search makes it sound like it's a video driver, but thats from all the nerdy overclocking sites, so unless there was a driver update that you installed I wouldn't start there..