This BSOD problem has been plaguing me for awhile, but it's recently changed.

Sometimes (most of the time) when my computer is idle for awhile, say when I go to bed at night and leave it on, I come back to find a blue screen.

At first they were always with ati2vag.dll or something similiar, so I thought it was a problem with my video card.

Now it's happening with ntoskrnl.exe.

The error is usually KMODE_EXCEPTION_NOT_HANDLED, but I've gotten IRQL_NOT_LESS_OR_EQUAL lately, too.

Sometimes, after I reboot from the BSOD and log in, I'll get another one within a few minutes.

This seems to be completely random. It happens often, but sometimes it wont happen, and I won't be doing anything differently.

It started happening about two weeks after I installed a new DVD drive, but since it took three weeks, I'm not sure if that is causing the problem.

So my big question is, besides "what's causing it?" is: does this sound hardware related?

My first instinct is to just reinstall Windows, but if it's hardware related, that probably won't fix it and I will have reinstalled for nothing.

So any ideas/suggestions would be appreciated. Thanks in advance.