Installed Quadro 285 in my new PC in x16 slot - works just fine - much slowly than GTS-450, but works, so I guess electrically x16 slot is OK
W7 automatically installed drivers 263.00
Next put GTS-450 into the same x16 slot - boot to windows desktop without any problems ?!?!
Ran for 10 minutes - OK
Started FurMark benchmark - PC froze at 97%
Put card back to x8 slot - all works fine
Last test I can do tomorrow is to put GTS-450 into Dell PC with DVI cable and run stress test again...
Not sure what else I can do since if I RMA card it will most likely come back with "no problems found"...