Power Supply $$$ ???

[Arclight]

Nice case of point; that BFG has 38Amps while a 520Watt Corsair has 40Amps. You'd think that the 650Watt PSU is per definition "better", but it's not.

Not saying it's a bad PSU, just that there's more to it than Watts. A PSU that delivers little Amps will still crap out in "hardcore" systems. Another thing is the Corsair has 1 rail; all 40 Amps are available to the whole system. The BFG has dual rails, meaning the available Amps are distributed. Not a bad thing, but it does make it more likely to overload one of them (not gonna happen with 38Amps total, so no worries).

Yes you may have used one of these brands for years without problems but bear in mind that no PSU lasts forever. Some PSU's die gracefully, quietly and alone while others commit murder, arson and suicide in that order.

In practice only certain dual rail units have much risk of exceeding an individual rails' limits. A PSU with three or more 12V rails will have much lower currents across its' rails then a dual rail PSU powering the same system. However a PSU with two 18A-20A rails that puts the CPU connector/s on one rail and all of the other connectors on the other rail can easily overload that other rail with dual graphics cards or a single very high wattage card like the GTX 295. But since PSU's with two 18A-20A rails naturally top out at around 550W most users will recognize to begin with that the PSU is too small for such a high end system.

http://forums.guru3d.com/showthread.php?t=287485

Nice read.;

It is true that marketing folks have told us that multiple +12V rails provides "cleaner and more stable voltages", but this is usually a falsehood. Quite frankly, they use this explaination because "offers stability and cleaner power" sounds much more palletable than "won't necessarily catch fire".