Dead On Arrival. Not unusual for a percentage of defective graphics cards to be shipped along with the functional ones
850 watts is more than enough to power 2 (or even 3) 5850's -assuming the power supply is of a reasonable quality and functioning ok.
the only other thing i can think of, the motherboard that im using has 4power molex plugs on it for the graphic cards, it said on the manual if 2 or more cards are installed you need both plugged in but i can only get one to plug in because the *****s who designed the board put the second plug on the side of the motherboard right agaisnt where the power supply is so unless i get a right angled 4 power molex it won't be plugged in
Probably just as easy to try the PCIEx16 4-slot or any of the PCIEx8 slots -unless they're all fried excepting the primary - save that one for last unless you're enamoured with the sound of motherboard beeping.:haha:
not funny guys lol the motherboard it like $600 worth lol not a cheap thing to replace lol