Gtx 560 ti problem plz help

ok

I have reseated this card twice, I got both 6 pin's in with a ocz 550 watt psu, i am running windows 7 64bit and the promblem is that my pc cannot detect the video card. the pc boots up and it's like small resolution before you put the drivers in, and I get to my desktop, the automatic install doesn't pop up, so I put the disk in, and every time i run the driver I get the following message on both the 266.44, 266.58 and 266.77 drivers "Install cannot continue, this graphics driver could not find compatiable graphics hardware". The fan's on the card are running and it's getting power. My motherboard is a Gigabyte ga-m68m-s2p running amd 920 phenom. I go to device manager and there's no display anywhere. in device manager the only thing I see is a code 35 error pci to pci bridge that I don't remember seeing before but might of been there since i only seen it when i was using the drop down arrow on all things. I am at a lose and will try pretty much everything anyone suggests, I used driver sweeper to remove all my older ati and Nvidia display drivers, but it's as if the pc wont' even reconize it's there and it's like my onboard is running atm. also I must not thou i don't know if it's important there's a bit of play in the gpu where it goes into the pci slot fartest from where you screw it into your case near the front, not sure if that's anything or not

When I put my old video card in a gtx 260, it installs right away and that code 35 error in device manager goes away.

Thanks.

my bios version/date is award software international, inc F4, 07/05/2010
and my SMBIOS version is 2.4