Need Help Choosing A PSU for SLI GTX 480's

[tinmann]

I just bought a second Evga GTX 480 to run SLI. I currently am using a SeaSonic X750 to power my system. Spec are:
Intel Core i5 2500K
Asus P8z68 V- Pro
Corsair Vengeance 4X4gbs @1600 DDR3
Corsair Hydro H100 cpu cooler
SeaSonic X750 watt psu
Samsung Spinpoint 1tb HDD
Liteon DVD burner with Lightscribe
TP-Link USB 2.0 wirelees adapter
Logitech G-15 Keyboard ( I just bought a Filco Ninja Majestouch-2)
Logitech G500 Gaming mouse
That's everything powered off the motherboard. Everything else has it's own power supply.

I've been looking at 3 psu's that I really like. The SeaSonic Platinum-1000
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151105

The Corsair AX 1200
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139014&Tpk=corsair%20ax1200

And the Antec TruePower Quattro Series TPQ-1200
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371039

The Seasonic is a little over priced for the 1000 kw range but how many Platinum rated psu's are there out there with SeaSonic's build quality? I can get the Antec relatively cheap off ebay probably but the inline capacitors might cause problems with cable management. The Corsair should be a no brainer but it's the most expensive of the 3. Finally, both the SeaSonic and the Corsair are fully modular. I really need some input and any help would be greatly appreciated.

 

[rolli59]

Any one of them will run your rig! The Seasonic gets my vote!

 

[iam2thecrowe]

http://www.geeks3d.com/20100414/power-consumption-of-two-gtx-480-in-sli-with-furmark-and-3dmark03/ you dont need 1000w. Your x750 will do the job so long as you dont overclock anything, but i would probably spring for an 850w model, but if your OC'ing the 480's, then yeah, 1000w isnt a bad idea.

 

[lunyone]

I would think your current Seasonic 750w PSU should be fine, unless your doing some extreme OC'ing.

I'm not sure why you need 1k PSU, but if that makes you feel better than I'd go with the any of the ones you listed. They are all good PSU's.

 

[tinmann]

I don't plan on OC'ing the 2 cards but maybe the CPU. if I can get by with my current PSU I'd be ecstatic. That's money spent elsewhere, maybe on a good 120gb SSD.

 

[rolli59]

Gaming load 668watts total system http://www.anandtech.com/show/4061/amds-radeon-hd-6970-radeon-hd-6950/24 Don't do a stress test though.

 

[ko888]

I don't plan on OC'ing the 2 cards but maybe the CPU. if I can get by with my current PSU I'd be ecstatic. That's money spent elsewhere, maybe on a good 120gb SSD.

How much of an overclock do plan on doing to the CPU?

At the i5-2500K's stock reference clock of 3.3 GHz the CPU VRM circuit will be drawing 75 Watts (6.25 Amps from the +12V rail(s)) at 100% CPU load.

At 4.3 GHz the CPU VRM circuit will be drawing 99.7 Watts (8.3 Amps from the +12V rail(s)) at 100% CPU load.

At 4.7 GHz the CPU VRM circuit will be drawing 134.9 Watts (11.2 Amps from the +12V rail(s)) at 100% CPU load.

For a reference clocked system running two reference clocked GeForce GTX 480 graphics cards in 2-way SLI mode NVIDIA specifies that the power supply should have a minimum combined +12 Volt continuous current rating of 63 Amps or greater and have at least two 6-pin and two 8-pin PCI-E Supplementary Power Connectors.

Your Seasonic X-Series 750W (X-750) has a combined +12 Volt continuous current rating of 62 Amps. There really isn't any spare capacity to handle any overclocking.

 

[tinmann]

I went with the SeaSonic 1000 watt Platinum. It came yesterday and I got it and the second gpu installed without too much hassle. Thanks for everyone's help.

 

[tinmann]

Best answer selected by tinmann.