my rig was running great this morning untill.... i had to finalize some cables running in the back. when i put everything back together and booted the pc my VGA LED on the mobo lit up and pc would not post.... so i opened everything back up checked all cables and tried again... same thing happend. what happened next was i tried each 7970 individually they booted fine no probs but when i install both and try to boot the led lights back up... i dont get it , it was runing great this morning now nuttin...... all the cables are connected properly the crossfire bridge is connected but it will not post with to cards... i played around with it some more and i managed to get into safemode now with both cards and both are recongnized in device manager but when i try to load windows up normally if freezes and locks up before i can log in?!?!?! any help would be appreciated and ty in advance...
my specs are: asus crosshair v mobo, amd fx-8150, 2x sapphire 7970, 1300 watt rosewill psu, 16gb corsaire vengence
Even if you get it working, an FX CPU would bottleneck the heck out of it. A single 7970 is almost twice as fast as what the FXs can handle properly. Two 7970s would mean that the majority of the performance of the two 7970s is wasted, even in a lot of games that are more GPU bound than they are CPU bound.
If you want to get this working anyway, then first make sure that your motherboard's BIOS is fully updated. Then, install the proper drivers for all hardware while in safe mode.
Also, make sure that your 7970s are in the proper slots for your motherboard. Basically, make sure that neither 7970 is in a slot that is not intended for graphics cards, such as a PCIe x4 slot. That shouldn't be a problem, but it might.
Another thing that you might want to try is re-installing Windows, except with both 7970s installed. That might help to force them to work properly. You could try it on a spare hard drive or a spare partition of your drive to make sure it works.