Hi Matt,
I was using last updated driver but I reinstall it just in case and it didn't work. I also have another problem that I forgot to mention; maybe they are related so; Actually my system is not that bad (like intel core i7 - 2600 CPU @3.4o GHZ 3.70 GHz, 8 gb ram, 64 bit operating system etc.) and it took so long to open city engine like min 10 minutes. I can open arcmap 10.1 in less then 5 seconds and when i start city engine, at least 10 minutes later I can open it and same graphic card error appears. but even that i have that error, program is allow me to use it without problem but maybe a little slower.
I really couldn't understand the reason of it. I'll happy to hear you.
Thanks.