Re: which computer is better
80-85% is the sweet spot for most psu's, so it'll run just fine for many many years.
I have probably a spare 100W around for psu degradation, and happiness.
I wouldn't personally build a system on a spare 20W over nvidias "specs" but stating it will be under powered is incorrect, it is just not great for future upgrades.
IF it wasn't a quality psu, things would be different for sure, but it is with good Amps.
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