Is my 750W PSU able to handle the following setup...

pospulsar99

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Mar 20, 2011
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Hey All,

I'm looking at upgrading my GPU's, and need to figure out if my PSU will be able to handle the load... I've looked at the extreme.outervision calculator, as well as the raptorxx calculator... and results are inconclusive... the former seems to indicate it'd probably be OK, but raptorxx shows much higher draw...

I'll post the system specs below... I'm looking at replacing my GTX 275 with a GTX 580, and using the GTX 275 as a PhysX card.

PSU - Thermaltake Toughpower XT W0229RU 750W ATX12V V2.3 80PLUS BRONZE

Motherboard:
EVGA E758-A1 3-Way SLI (x16/x16/x8) LGA 1366 Intel X58 ATX Intel Motherboard
CPU:
Intel Core i7-920 Bloomfield 2.66GHz LGA 1366 130W Quad-Core Processor
RAM:
6 Sticks DDR3 SDRAM - CORSAIR XMS3 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) (times 2)
Video Card:
NVIDIA GeForce GTX 275
Regular SATA:
3 HDDs
High rpm SATA:
1 HDD Raptor
DVD-RW/DVD+RW Drive:
1 Drive
USB:
2 Devices (1 of which is a Bose speaker set)
Fans
6 Fans 80mm case fans; 1 CPU heatsink fan
 
Because the GeForce GTX 275 is only being used as a dedicated PhysX card I highly doubt that it will ever be drawing its maximum of 18.25 Amps from the +12 Volt rail.

Those calculators are assuming full GPU load on both the GTX 580 and the GTX 275 to arrive at their recommendation.

If both graphics card were running at maximum GPU load you will reach/exceed the limits of your Thermaltake Tough Power XT W0229RU power supply unit's +12 Volt rail's maximum DC output capability.
 
The first PSU calculator you used is more of the standard and generally provides better results.

I would be concerned at the least because Thermaltake doesn't make phenomenal PSUs, so I don't know how much power you'd really get from that 750W.