I just want to share my findings here since this community has often helped me with other problems in the past (besides, not sharing would be a waste of good testing data 
). Please forgive the double post as this one explains the problem and how I figured it out, while the next one gives details of the actual testing results.
I've been having instability issues ever since I put together my system 6 months ago, but I suspected my graphic card since I've always had crashes during gameplay and with videos, the error always being "amdkmdap stopped responding". Last few weeks though I had random crashes of firefox, mediamonkey and so on and I started to suspect my cpu and motherboard. I did not suspect my RAM (anymore) because I had run MemTest86 3.5 for over 8 hours over night on a couple of occassions and it never found any problems. However, I finally managed to nail down the problem to one of my GEIL 2GB PC3-1066 memory sticks thanks to having two nearly identical systems, a lot of careful testing with Prime95 and a few games that consistently crashed.
On two different systems the PC becomes consistently unstable when that one stick of RAM is used regardless of slot used so I'm 100% confident that the stick is faulty. Prime95 will fail quickly for blend or large FFTs, but never fails for small FTTs and when running Civ V (Dx11), Guardian of Light or Blood Bowl I ALWAYS get amdkmdap errors with the problem stick and NEVER without it. Guardian of Light and Blood Bowl will usually run for a while before failing and may survive the "gpu crash", while Civ V (Dx11) tends to crash almost immediately most of the time. I now also wonder if my long running issues with ATI 5770 were all due to the faulty RAM, or if that was a seperate issue finally resolved by the bios and driver updates I've been doing.
I still need to RMA the memory pair and explain that the problems do not appear in MemTest86 - hopefully overclockers have better testing techniques that will confirm the faulty memory and I can get a new pair with no issues this time.
). Please forgive the double post as this one explains the problem and how I figured it out, while the next one gives details of the actual testing results.I've been having instability issues ever since I put together my system 6 months ago, but I suspected my graphic card since I've always had crashes during gameplay and with videos, the error always being "amdkmdap stopped responding". Last few weeks though I had random crashes of firefox, mediamonkey and so on and I started to suspect my cpu and motherboard. I did not suspect my RAM (anymore) because I had run MemTest86 3.5 for over 8 hours over night on a couple of occassions and it never found any problems. However, I finally managed to nail down the problem to one of my GEIL 2GB PC3-1066 memory sticks thanks to having two nearly identical systems, a lot of careful testing with Prime95 and a few games that consistently crashed.
On two different systems the PC becomes consistently unstable when that one stick of RAM is used regardless of slot used so I'm 100% confident that the stick is faulty. Prime95 will fail quickly for blend or large FFTs, but never fails for small FTTs and when running Civ V (Dx11), Guardian of Light or Blood Bowl I ALWAYS get amdkmdap errors with the problem stick and NEVER without it. Guardian of Light and Blood Bowl will usually run for a while before failing and may survive the "gpu crash", while Civ V (Dx11) tends to crash almost immediately most of the time. I now also wonder if my long running issues with ATI 5770 were all due to the faulty RAM, or if that was a seperate issue finally resolved by the bios and driver updates I've been doing.
I still need to RMA the memory pair and explain that the problems do not appear in MemTest86 - hopefully overclockers have better testing techniques that will confirm the faulty memory and I can get a new pair with no issues this time.
