Secondary CPU Error BSOD

I have a desktop running an Intel Core i7 950 cpu. I love it. The thing is fast. There are faster on the market, sure. But it is fast enough for what I want to do. OK, I would like faster, but it is fast enough.

What do I do? I built this machine as a gaming computer. I did other things on it but gaming was the heaviest. Recently, however, I have gotten into 3D animation with Blender. I have stressed this machine like never before using Blender.

I had some heating issues last year. Turns out the stock heat sink for this processor doesn't like to stay attached to the motherboard. Kind of important. I changed it for a $30 model from Fry's and it works great now.

Until last month. I left it rendering over night and woke up with this

My heart sank. Now what is wrong with my beloved machine. Reading online told me that the problem is with the CPU. Since I have a quad core processor, one of them apparently is the primary processor and the others are secondary. Mine is hyperthreaded as well, so there are 8 "logical" processors. Clock interrupts control the cycles of a CPU. You know how they are measured in Hz? GHz, MHz, even in the day KHz. Well that is the measure of the clock. Every time the clock "ticks" it sends an interrupt code to the processor. This steps the CPU to the next instruction. If these clocks don't arrive in sync your computer gets very confused. This is what was happening on my computer.

It would do this every time I stressed the system for a month. Sometimes it wouldn't even blue screen, just lock up and do nothing not even move the mouse.

It wasn't just Blender that was causing this. Handbrake and Battlefield 2 (the game I built this machine for) were causing this as well. 

I took my computer apart and reseated the CPU by taking it off the motherboard and putting it back on again. I also reapplied the thermal paste to my heat sink. I rebooted and got not a blue screen but the lock up symptom.

I rebooted again and went into the BIOS. CPU temperature was normal, about 45C. I reset the motherboard settings to "Optimized Defaults" and rebooted. Started up fine. Went into Blender and opened my current scene. I started it rendering. After about 45 minutes no problems. That hadn't happened in a long time. So I went to bed, but had Fing on my phone set to ping my computer. When I would wake up in the night I would hit ping and see if my computer responded. It did, all night. 

It has been three days now of heavy Blender use. I even ran Prime95 on here to see if that could crash it. Rock solid, again. 

If you are having trouble with this error, try reseting your BIOS. That seemed to do the trick for me.

Update: Well, I haven't had the BSOD problem again, but the computer has started just locking up. I am going to back up and reformat this weekend. Hopefully that fixes it.