Instead of looking for ATX, look for EPS12V. But look carefully some of these power supplies may me marked as ATX since they may come with an adapter to convert the 24 pins to the 20 pins. Also keep in mind that at least ABIT 24 pin power motherboards will still work with only the 20 pins. I don't know about other brands of motherboards but I think it is the same with them all since I think it is part of the new standard to be backwards compatable.
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