Been having some issues with my GTX 560ti 2GB ever since I got it. Made a few threads about them before (look them up for more info), every other time or so it fails to power display anything and causes a delayed POST when turning on my PC. I've had two 560ti 2GBs like this and a third with a chipped/damaged PCI-E connector and pins. All were new in box.
 
Recently my friend got an EVGA GTX 560ti 448 FTW. So I tested that in my PC for a few days. And it works flawlessly, just like my EVGA GTX 260 and my other friends HD6950 flashed to 6970. After removing it and reinserting my GTX 560ti 2GB, the same issue came back after a shut down/power on.
 
Is there any reason why a GTX 560ti 2GB would not work in my PC, but a GTX 560ti 448 FTW would work flawlessly? My specs are listed below:
 
ASUS M3N78 Pro - tried two different BIOS
Corsair XMS2 8GB 4x2GB DIMMs
AMD 965
WD 1TB FALS
Antec Earthwatts 500 - upgraded to PSU below to help fix the issue
Antec Earthwatts 650
Samsung 223F DVD/CD
Viewsonic 19" monitor using DVI
Samsung Syncmaster 24" (tried my PC on my friends monitor and it also got the same error)
Win 7 Pro 64bit
 
Nothing ever OCed of course.
 
I am just failing to see why all of those other video cards listed, including a 560ti 448 FTW, would work while a 560ti 2GB doesn't. Any input would be appreicated.
 
On another note, I wish there was a new $250 GPU that was a worthy upgrade over a 560ti. These new $500-600 GPUs are completely out of my reach.