Which PSU for Dual Core SLI rig

I have been looking at a few - but do I need dual, triple or quad 12v rails?
All the PSU I am looking at are SLI certified, but my new Dual Core is going to suck major juice once I get it up a bit higher.......I want one with plenty of juice for the CPU.....I have the Neo480w just now...can anyone recommend?

I think the thing to do is get a PSU with a high current capacity on a single 12V rail. eg, something like the OCZ 520 Powerstream

A single 12v design would be the best way to go, but the quad units you listed will work too (though one 12v rail will not be loaded). The Akasa and Silverstone 650W units are the exact same Enhance made PSU - I'd look for the cheaper one. However, this model is reputed to be loud. You can get by with the Fortron Epsilon 600W model since 12v2 will have no load - it still has a 44A combined 12v capacity.

Some I don't see on your list but deserve a look are the Silverstone 560W, OCZ Powerstream/Topower P6 520W (avoid the 600W non single 12v models), Zippy over 460W, and Etasis EPAP-560 (which is the same unit as the Silverstone 560W), and the Sparkle FSP550PLG-SLI.

Edit - just noticed you're running Intel... I'd strongly suggest a single 12v unit rather than any quad 12v unit short of the Zippy, PC P&C, or Etasis/Silverstone 700W+ split plane SSI units. I hear the 650W Silverstone/Akasa comes with an adaptor that adds 12v1 and 12v2 together, but don't quote me on it. Still looking into whether the Fortrons can handle combining rails.

Oklahoma Wolf said:

I hear the 650W Silverstone/Akasa comes with an adaptor that adds 12v1 and 12v2 together, but don't quote me on it. Still looking into whether the Fortrons can handle combining rails.

Click to expand...

I can confirm that the adapter does combine 12V1 and 12v2 together. However, the new version of Akasa 650W does not include that 8pin to 4pin adapter anymore (they decided to have both 8pin and 4pin connectors coming out of the PSU) so I would recommend getting a dual core motherboard with 8pin connector if this PSU is used. This is the same situation for the Epsilon unit from Fortron, they deploy a detachable 4+4pin connector so if the motherboard only has a ATX12V 4pin connector, you will only be able to use one of the 12V rails for the CPU.

With more dual core capable motherboards now utilizing 8pin connectors, I wouldn't be worried too much about getting quad-rail units though.

i would say an ocz 520w .. the 600 watt has split 12v rails

The OCZ Powerstream520 should be enough for even two 7800GTXs in SLi. Anything above that PSU would be the PCP&C 510.

Thanks for the advice guys, will get my thinking cap back on and look at some of the other PSUs mentioned

for a big P4 overclock, single rail +12V is highly preferred

the ocz 520w sli certified version should easily do the trick. thats what TomsHardware used for all their sli testbeds

What about the PCP&C 850SSI - that has a phat 30A main 12v line, and 2 for other stuff?
I am thinking either that or the TC510 SLI with a 34A +12v, single rail - surely 3 has to be better than 1 as long as the main CPU line is fat enough?

markodude said:

What about the PCP&C 850SSI - that has a phat 30A main 12v line, and 2 for other stuff?
I am thinking either that or the TC510 SLI with a 34A +12v, single rail - surely 3 has to be better than 1 as long as the main CPU line is fat enough?

Click to expand...

That one is 16A+16A+30A, with a 54A combined maximum - not recommended for Prescott overclocking, and one of the two main 12v rails would go unused unless you ran dual CPU's. The 510W or the competing Zippy PSL-6701P 700W and its single 45A 12v rail would be better options.

Go antec, i know somone who puts together servers, and he says that they are most reliable.

@Oklahoma Wolf - AFAIK the new board I am getting will have the 8-pin connector (P5WDG2-WS), so that will help as it will use all the power for both CPUs.
I am going to test an FSP Epsilon 700w that I am getting on loan, which is similar to the PCP&C 850 design, if its no good I will buy the PCP&C TC 510.

EDIT@ MrGreen - I have always used Antec in the past, but their PSUs are just not big enough for my latest applications. I had one catastrophic failure with an early Neopower which went up in smoke (literally) - think it was a bad cap as the PSU kept working but sounded and smelled horrible. I told Antec and they sent me a brand new one out straight away.

markodude said:

@Oklahoma Wolf - AFAIK the new board I am getting will have the 8-pin connector (P5WDG2-WS), so that will help as it will use all the power for both CPUs.
I am going to test an FSP Epsilon 700w that I am getting on loan, which is similar to the PCP&C 850 design, if its no good I will buy the PCP&C TC 510.

Click to expand...

I'd be interested in the results since I plan to either combine 12v1 and 12v2 on the 600W I have coming as well, or use 12v2 for the other video card.

Theoretically, you should have up to 30A available that way for the CPU (not that you'll need that much), which will still leave 20A for the other two 12v rails. Should do ok, but the results remain to be seen.