I just got my second Sapphire Vapor-X 5870 today and put it in. It started to heat up really quick and I didn't hear the fan on the second card when I turned the fan speed up to 100%. I pulled the card out of the slot and powered the PC on and the fan didn't spin. So naturally I thought that it was dead so I swapped cards and put my other 5870 in the second slot and the same thing with the other one plugged into slot 1, the card's fan in slot 2 would not spin. So no matter which card I put in slot 2 the fan will not spin. I made sure that the both 6 pin cables are plugged in and still nothing. I had 2 4850s in there and they both worked fine. Any ideas on what could be causing it to do this?
I don't know what the power requirements are, I imagine in xfire mode it's alot less than 2x4850s, but just because I know it'll get asked, what kind of psu do you have? It could be a power issue, or somehow you've managed to damage the 2nd slot? Does CCC or device manager recognize both cards?
Yes, both cards are recognized howerver in GPU-Z the card in slot 1 is seen as being connected to a PCIE x16 slot while card 2 says it's in a PCIE x8 slot. The slots are both x16 as they were when the 4850's were in there. The power supply that I have is the factory 750watt that came with my Alienware PC.