Hi everyoneI left my computer on last night-I was completeing a flight from KLAX toEGLL in the levelD 767.When I returned to the pc this morning the screen was black,the fsx was still running and there was the following message:'display driver nvlddmkd stopped responding and has successfully recovered'.I have googled this and it seems lots of people have this problem.Do many of the fellow simmers have this problem and have we found a solution.My systemvista ultimate 64bit,intel 6600(oc @ 3.35 on air)8800 ultra xxx grahic by sfx,with the latest driver from nvidia site.msi p35 neo2 motherboard-no bios update.This is a one week old fresh reimstall-I have only fsx on it.I hope someone can help.Qas

I am virtually certain that this is a sign of instability in your overclock. I had exactly the same problem at 4.32Ghz on my E8600: on an FSB of 480MHz and CPU multiplier of 9, this gave me the sweet-spot of 1600MHz for the RAM. The thing could run Prime95 indefinitely on these settings and it would work fine under FSX for my flights, which are usually well under 3 hours. But if I left it on for more than a few hours, this error would crop up. Pulling back the FSB speed by just 4MHz has restored stability. Naturally, I tried everything I could think of first - including different drivers, latest DirectX and Vista updates, and so on. I also tried different voltages and skew settings etc in the BIOS and perhaps if I were more skilfull at overclocking, or less ambitious with the RAM timings, I could eventually have got everything better tuned. But the law of diminishing returns quickly kicks in here. The thing works fine at 4.28Ghz, performance isn't noticeably different from 4.32GHz, and I can either spend time searching for a magic combination of voltages and skews or whatever, or get on with life and learn to accept that I had simply over-clocked beyond my or my PC's abilities. A long-winded way of saying: try reducing your FSB MHz a little.Tim

Many thanks Tim-I will do this immediately and feedback on the outcome.Qas