So I didn't have any issues for 5 days so I hoped the problem was gone. Unfortunately, it happened again today WITHOUT the game running. Once the usual blue screen happened ("DRIVER_POWER_STATE_FAILURE"), the computer blue-screened again, this time with a different error that I hadn't seen before. It said something like "IRQL_NOT_LESS_EQUAL," but I'm not sure if that's exactly right-- the screen disappeared after a couple seconds.
I have a sneaking suspicion now that the problem is my RAM, so I'm going to run a memtest as soon as I can get my hands on a blank CD (I'm a college student). I figured I should upload this latest problem in case it sheds any light on the issue.
Thanks for your continued support.