TjFNQFire up GPUZ---- and look specifically at the Sub vendor, Bios Version, Bus width, Bandwidth etc. and make sure there are no "unknown" labels in those boxes. Also make sure the device id's and bios version match the card. You mentioned folding? I thought that was only for ATI cards not Nvidia, don't quote me on that. Also how have you connected the 6 and 8 pin pwr connectors? Hopefully not daisy chaining the one cable out of PSU. Lets us know
SajinLet us know how putting the stock cooler back on goes.