9800gx2 game crashes

[Abren]

Hi all,
I got a new rig as follows:
9800Gx2(FW 175.19 drivers)
MSI x48c platinum MB
OCZ 1333ddr3
1 75GB raptor,2 150GB raptor HDD
Coolermaster Real power PRO 850W (Peak 100w) power supply
Water cooled CPU (Intel QX9650 3.0 ghz)Vista 32bit

Now the problem is that Creed Assasins(DX9) hangs up either after 2mins of startup or anytime between within 20mins.Sometimes the system itself freezes randomly and sometimes i get artifacts in game and in windows(where everything seems to be corrupted)
Also Company of heroes shows pixelating or artifacts after 10-020mins of gameplay.
CPU and GPU are running pretty cool, Memory check has been fine.
I am ZOMG'd and disappointed.(:
Please assist

[bknblk]

Assuming everything else is set up properly, it sounds like you have a bad card.

[Abren]

I am changing my motherboard to 790i ultra. Hopefully that will solve the problem
Also am going down to drivers 175.16.SO fingers crossed for Tuesday

[David power]

Make sure your GX2 is cooling its self. I have had 2 of them both will keep rising in temp until they die unless I use rivatuner to set the fan speeds to 86%, this keeps the card nice and cold,

what temps does the card run at idle?