The very same problem has plagued me since March 29th and it has been driving me nuts. I have gone through a TON of troubleshooting too and had replaced a hard drive and a sound card. At times I even felt it was fixed then sadly found out an hour later that it was not. My PC is only 3 years old and I felt it was not old enough to be experiencing problems.
Well today I am confident I found the solution.
Below was the exact error I was receiving:
This would randomly occur in games normally a few minutes in. Just prior to it horrible loud static would come through the speakers. Sometimes it would not blue screen at all it would just reboot or go to a black screen and not recover. I have even had this happen watching YouTube.
What I did to fix: (some of these may not be relevant but it is what i did.)
1.) I found a post where someone reseated their CPU and stated there must have been dirt on the pins because it started working afterwards. I did not see that at all on mine or understand how that could practically happen but I did find that my CPU was stuck in the socket even though I had the lock bar released. After I got it to release with much work I reseated it. I think the weight of the heatsink may had jammed it in. I had had problems in the past with too much pressure on the CPU and it caused games to freeze up. So I reseated it and applied new thermal paste.
2.) I have four DIMMs. I took all of the ram out while I had the CPU heat sink off and make sure I had them paired in accordance with their serial #s so they were in their original sets.
3.) If you have a video card with dual DVI ports try the 2nd DVI port if you are using the first one and vice versa. My thoughts today that maybe one of them went bad or if I used the 2nd one the data flow would be different and it would be less prone to error.
From what I read STOP errors tend to be hardware related. I think my CPU just got wedged down or the 1st DVI port on my video card went bad.
Not sure which but it has been working great even after powering it off and rebooting.
Hope this helps. If not post a response. As I said I have been troubleshooting for nearly 2 months so I can tell you other things I did / tried. Highly frustrating issue.