EDIT: In response to Buck47's post, on 2.5 hours of sleep, I read, "Did you [mean] memtest?". Hence what caused the post below. Sorry. But non-the-less, some good info is below.
Nope. I meant CPU-Z.
MemTest tests the memory, but I've still had faults in mem chips even after it tested them OK. Not reliable IMO, but then again it's been years since I've used it. I kind of like Prime95 actually for my mem testing (over a few days, that is).
CPU-Z was mentioned for him to check the timing the BIOS is forcing the chips to run at. If it is not adhering to the SPD timings from the manufacturer of the chips, then either the BIOS is detecting a fault or it simply doesn't like the chips and is trying to compensate - or the chips are faulted and the bios is adjusting the timings to compensate "for the most part" until his system hangs.
Basically looking to see what the bios is forcing the timings to vs. the SPD has been a good indication of a detection fault for me. If the timings are dead-on, then it most likely is the chip(s). If the timings are off, I'd look more at the bios/mobo combination and mem compatibility. Most of the time, it's been high-end memory overclocked in mobos that weren't detecting the SPD correctly for me.
I say to review each chip seperately because I've seen mobos take a "matched pair" of sticks, and give different timings (when overclocked) per stick when reviewed individually.
Originally Posted by Buck47
Did you run memtest? Go to www.memtest86.comDownload and test each stick individually. Take a while - you want to get about 6 passes on each stick. Make sure you test them in different slots as well.If either of them fail, RMA.