I know what you are thinking already, that it is the power supply, however I have been through three. The one i have in now is an antec 650w and the 2 12v rails output 38, much more than the 660 needs so that is not the problem. When the card is in, the PC will not start. It is the ASUS model. Is this caused by the graphics card being faulty, or a motherboard problem? Any reply is appreciated.
Are you sure you have all the proper power connections into the graphics card? Try switching them to alternate ones or use the usually included cable with the video card and try running off the molex connecter. Also double check that you have the proper connections into the motherboard for power. I remember some at one point that would take an extra 4 pin molex connecter in there to supply additional power for expansion ports and other stuff. By not starting do you mean that you have absolutely nothing coming on like no fans or any lights? No beeps? If you have another pci-e lane that will accept the card try it in there or perhaps the one its currently in isn't seated properly( maybe not enough clearance for sata ports or heatsinks?). Also have you tried an alternate dvi port or hdmi port if you can on the graphics card or monitor? Check this stuff and let us know if any of that works.
Tried the other PCI slot, nothing. Triple checked every connector, its all good. When i start, No fans, no lights, nothing happens. Also tried instead of using the power button shorting the two power pins on the mobo, but the power button isnt the problem either. Would running the graphics card on a power supply that is not as good, like the 12v rail was barely meeting requirement, cause the graphics card to short or whatever? I still have the card under warranty so replacing it is not a problem.
Well to be honest Antec isn't my favorite brand. I've had two fail in computers mind you it was a few years back but i'm stubborn that way and when i get burned I won't touch the brand again. Also have you tried a different power cord into the back of your computer? If you don't have spare one try the one that most monitors come with out of your own monitor just to test and see. It does seem odd that it wouldn't power up at all with the card in but will without it. By rights I would think it should power up and the vid card as well but if you tried to load a game it should crash when the demand for extra power got too high. Unless the card is demanding just so much and the psu doesn't come anywhere close to 650w.
Keep in mind, my PC starts perfectly fine without the graphics card. Could this be caused by the card running on a lower quality power supply with the 12v rail not supplying enough and running it like that for a while? because that is what had happened before I got the antec
I suppose it is possible but if you had by chance another video card with maybe a tad less power requirements to test or another spare computer to test your current video card in that would be good before going out and spending money on a psu.