You probably have a driver problem.
Some guys on sukhoi forum had problems with 29x.xx drivers,but not like yours.
http://translate.google.com/translat...008%26page%3D3
You could try to go back to older ones that you had installed.
Also if you have problems it will be wise to use Driver Cleaner or Driver sweeper ,
to be shure that you have clean installation.
I would test that card with Furmark to check stability and temperatures.
Good luck!