I just got a VisionTek R7 260X 2Gb card to replace my HD 5770 1Gb. I removed the drivers and catalyst stuff, then powered down. Swapped out the cards and the machine would hang at the first bios screen. I noticed that my usb lights on my keyboard weren't on and swapped over to an old keyboard thats not usb. then machine still hung at the bios screen. I then removed all usb devices and the computer booted to the login screen then gets stuck in a loop on rebooting, goind to the login screen then rebooting again. Took the card out check that I had it seated and hooked up right. Still doing the same thing. Then I swapped back to my old card and plugged in my usb stuff and it boots like normal with the old card. I dont get it. My motherboard is a ECS A780gm-a v1.1, I have 4Gb of DDR2 Ram, An Antec Pure power 550 power supply and an audigy 2 ZS funning windows 7 64. Help PLease