Artifacts at stock settings SLI

I finnished Doom3 and the expansion pack last weekend and now I am getting some artifacts in 3d games. It actualy started when I was about half thru the Doom3 expansion. I also had the SLI tearing issue before I updated to the 77.72 drivers but now that is back as well and I have not changed drivers. I had done some overclocking of the cards. I used riva tunner to enable bios level overclocking and then went back to the nividia display to auto clock the cards. I am wondering if the overclocked settings have messed up one or both of my 6800gt's. Is there a test of some kind I can run to findout?

I rolled back my drivers to the ones that came on the cards install disk and all is well!? Must have corrupted the driver some how!?