X-bit Labs has compared 450W, 550W, 650W and 1000W power supplies from Corsair:
Power supplies and computer memory seem to have little in common except that both are computer components. This common feature doesn’t sound to me like a good reason why many well-known memory makers such as OCZ, Corsair, SuperTalent have begun to produce power supplies. The trend is obvious, however.
Well, explaining phenomena of the computer market is not my job. Instead, I will check out how successful the manufacturers are in this kind of business diversification. This review will cover Corsair’s power supplies.