Re: PSU for gaming computer
The Antecs are your only choices in that list.
My suggestion would be a 650 Antec Earthwatts. You'l need your old power cord btw.
While 550W is fine, I'd go to 650 so you have wiggle room for old age and bigger gpus.
If you can find a Corsair tx or txm in 650 for a reasonable price, its another great option.
Foldie = i7 950@ 4.0Ghz Gigabyte x58a-ud3r EVGA 970 SC Corsair H100 Corsair hx520 3x2gb OCZ Gold Corsair 650D
Woohoo = L5639 @3.1Ghz EVGA SR-2 gtx 260-216 Hyper 212+ Corsair 1050hx 6x2gb Corsair XMS3 Blackhawk Ulra
Alienware 18 - SLI 770M 4700mq 16Gig