I've been having a constant problem with my custom built PC. All started about 2 months ago I had been experiencing crashing and screen freezing issues. After much trouble I finally found a shorted wire on the bottom of my pc from a side fan molex power connector. Every time I would try to run both of my Nvidia 9800GX2 graphics cards I would not be able to run them in normal quad SLi setup I would only have the choice of running in Tri Sli. When I would go to Device manager one of the 4 display adapters would have an "!" and when you right clicked then properties the text box would say "Windows has stopped this device error 43". I would then fill out a RMA thru BFG and send the card in for repair. After getting the card back and reinstalling it would do the same thing, so I'd send it out again blah blah..after repeating these headaches for 4 card replacements BFG upgraded me to 2 Nvidia GTX 285's in trade for the 2 9800GX2's. Before I installed both together I thought maybe the shorted wire had messed up my power supply (1100W) so I decided to replace it before attempting to run both 285's in SLi. So I buy a new PSU a BFG ex-1200, and install everything and fire it up and...BLAM I only get one of the 285's working the other has the error code 43 and I can't enable dual GPU Sli. I noticed that it is only the card on the bottom PCIe16 slot (Slot 3). I have 3 PCI slots on my Mobo but when I try putting the cards in slots 1 and 2 my bios when I first turn on the PC tells me that I must move the card from slot 2 to slot 3 in order for SLi to work. So I can only use slots 1 and 3, so I move the good card from slot 1 and put it in slot 3 and the bad card from slot 3 and put it in slot 1. Fire it up and now the slot 1 card which windows just told me was bad error 43 is working fine and the previously ok card now in slot 3 has the error 43. So before I go any further I was wandering if anyone had any suggestions because all I can come up with is that maybe the shorted wire did more damage than I thought and the 3rd PCIe16 slot is bad so I gotta get a new motherboard. My specs: Mobo-EVGA Nvidia 790i Ultra, GPU's- 2 BFG Nvidia 285, PSU-BFG ex-1200, Ram- 4gb ddr3 pc1066 4x1gb, Windows 7 Ultimate 64bit, Intel Q9770 quad core processor. All my drivers are up to date and bios up to date.