Asus 680 SLI issues

I have 2 of these beast asus gtx680 dc2 4gb sli in a asus crosshair v formula-z 990fx motherboard with 8350fx amd and 16gb of ram 2133mhz and 1250 seasonic gold powersupply.

The problem is when I enable SLI I get direct x crash of any game I try. Borderlands2, cyris3, metro last light, bioshock infinte, battlefield3, etc. Now if I turn v sync on I can play cyris 3 but 99% of the I get reduced instead of increased frames rate and I get massive flickering. Almost like one of the cards is not keeping up. Now if I play in windowed mode I have no problem with any of the games. I have tryed just about everything and I am just about to give up and sell the cards on craiglist and get a dam titan or 780.

I have clean installed windows 8 3 times. I have even installed win 7 once. I have bought new sli bridges (4 different ones tryed). I have moved PCI express slots. I have tryed my old power supply corsair 750. I tryed different slots and new pci cables on the seasonic power supply. I have even rma'd the cards to asus.


Anyone have any idea before I give up and sell it and start a new gfx system. Thanks

Have you tried different drivers?

Yes Serveral ranging from the oldest win8 I could find to the lastest beta drivers.

 

Ok I found the solution. I took my Video cards out and put them in my buddies Intel system and they work, with the same drivers. So I am thinking Motherboard has sli issues. Going to try an old motherboard this weekend. Sure hope it fixes it. I am just happy the video cards are good. They were not cheap.

Update on this issue. I changed motherboards. It did not fix it. But after troubleshooting with ROG Asus Forums I retryed updating my video bios and it fixed it. I just wish their original gpu tweak work the first time. I would have fixed it long time ago. Probably a win 8 issue though. Problem Fixed