BSOD Driver IRQL Not Less or Equal

[FrostyKzink]

Hello! I am having BSOD issues. It happens most often when I'm playing games (specifically during Rift), but it is still happening occasionally when the computer idles. For example, I'll leave for work in the morning and come home to find the computer reset itself.

Here are some specs:

Windows 7 Home Premium 64-bit
It is the original OS that came with the system, but I had to reinstall my OS in late February when it wouldn't start and Startup Repair failed to fix it.

I got the system in November 2009, so it's just over a year old.

Any help is appreciated! I can provide whatever other information you need to figure this out.

 

[FrostyKzink]

Bumping in hopes of getting some assistance.