I think this guy is pretty honest, my friends use him often for purchasing computer hardware and parts, and have known him for years. I was also present at the time when he was replacing these parts.
The other thing is that I just finished running Prime 95 and did the blended torture test, and it did not turn up any errors. I let it run for about 10 hours with my CPU and memory pretty maxed out.
I also did not overclock this machine in any way. I'll also give that chkdsk scan a shot and see if that helps. If H2S04 could give me instructions for setting up that test between my desktop and laptop, I will give that a shot.