Quote Originally Posted by ppost View Post
One of your cards work, so there must be something wrong to the installation on the others.

If there were mis-contact, it should still run 1-2 minutes from cool before the system shut down by itself (8800 does that, and GTX280 is not hotter than 8800 on idle). Have you noticed any burnt mark/smell? Suggest try back the stock fan block to see if they can still operate first.
No smell at all, the stock case was junked!!