Larger than necessary PSU?

Shibuya

Commendable
Feb 28, 2016
3
0
1,510
So the system I'm planning to assemble soon needs about 320W according to my calculations but there's a sale going on at a store nearby that has the Corsair CX750 (750W) for about half price. Is there any reason not to get the Corsair aside from the whole 50% efficiency rule? I'm guessing it won't run up my electricity bill? I want the build done by this week so buying it locally would be plus.
 
Solution
It will not be an issue.

While power supplies do hit peak efficiency at about 50-60 percent load. They still strive for high efficiency in the 20-100% area anyway.