I was told that a psu with a single +12v rail was better than a multi rail. I have on this computer a 750 pc power and cooling w/60a. I am on the fence wether to change out this one which supplies my GTX 275 with the other one. To my understanding the 275 uses more power so i figured I would use the thermaltake. Am I correct to assume this or should I swap it out?
No need to swap. modern 28nm cards use less power.
As earlier, the number of rails is an artificial safety spec, not a performance spec.
For some time, PC P&C who make great psu's were touting the benefits of their single rail and non modular construction.
Over time, both have been shown to be a non issue.