Hi, When running simulator, I see black splotches here and there.I ended up getting error message saying "Nv4 disp display driver has stopped working normally". I have a Nvida 6800 with 256mb video card. 2.39Ghz,1.50 Gbram. I have this card since march 2006 but I have not updated drivers, could this be the problem? Several times simulator stopped running and locked up so I had to reboot computer. Thanks for help.

Hello, First, is there a temperature reading in the Nvidia utility settings? Two, if it is running hot, this could cause problems. Check that your system doesn't have dust build up around the fans and heat sinks. If all is good on that end, it can't hurt to uninstall your display drivers, then reinstall them. I recommend a program called Driver Cleaner Pro. It is free over at TweaksRus I think. After you remove the drivers through add/remove programs, restart and select safemode. After you are in safe mode, run the program, after it removes any lost files left behind, restart in normal windows and reinstall. Important: Just make sure you follow the instructions carefully, or you could end up uninstalling things you shouldn't, like MB drivers and such EX: If you have an Nvidia chipset motherboard. I hope this helps. I don't know if anyone else here has other suggestions. Good luck. Let us know how things work out.

One thing you also might want to check, is your PSU, how is the rest of your system compiled?. Could be heat buildup or lack of power going to the card.

Hi, Thanks guys for you help. I used suggestion about dust and overheating, you were correct. I cleaned up and things are perfect. Thanks again.

Good to hear things are well once again. I check my system every other month. If things are starting to get the slightest buildup, I blow it out with compressed air. It's also a good idea to make sure you have enough fans to circulate the air flow and move the heat out of the machine, also check the operation of them as well. They can stop working after sometime. Have a good night.