That’s the thing, there’s no BSOD (at least not long enough for me to actually see it or even get any kind of hint of it). Ironically, the last time I remember it happening (in front of me) was when I was about to click on a link of how to backup the hard drive. What has me convinced that it’s a failing HDD is the sounds the drive makes at time.
It first started Saturday night, after I downloaded a game and played it for a few hours. It just restarted in the middle of the game, then wouldn’t start up again until after I turned it off and did a system restore. It’s starting up now, but restarts at random, and then doesn’t even go into the checkdisk process, which otherwise starts up when I turn off the computer without going through the shutdown process.