HELP ! Please , Choose me PSU

[pratmodi]

My specs -
Phenom ii x4 960T
SLI GTX 550Ti x2 in SLI
8GB DDR3
DVD RW
SLI motherboard
i might just slightly O.C. cpu

but i m confused and afraid of the fact that my last psu burned my 3 gpus .
so i was quite pissed off by my PSU .

now i wanna be 200% sure about this .

i dont know about Efficiency and other things but i want the best psu so out of these two which one should i get ?

- Corsair TX 750
- Corsair TX 850

is 750 enough ? extreme vision calculator showed 520W , newegg showed 630 W , and others showed around 550 W.
i think as TX 750 delivers average 84% efficiency, it should deliver only 630 out of it and TX 850 around
714W for 84% efficiency.
PLeasse help , becoz tx850 is way too expensive.

 

[mcnumpty23]

tx750 will run that fine

i am running higher spec pc than yours and heavily overclocking the cpu to 5ghz and overclocking my gtx570

on a tx750

 

[Rugger]

A system running two GTX 550TI in two-way SLI requires a 650W PSU with at least 44A on the 12V rails and two 6-pin PCIe power connectors.

The Corsair Enthusiast Series TX750 V2 with 62A on the 12V rails and four 6+2 Pin PCIe power connectors is more than sufficient for your build and OCs.

The Corsair Enthusiast Series TX650 V2 with 53A on the 12V rails and two 6+2 Pin PCIe power connectors is also sufficient for your build and OCs: http://www.newegg.com/Product/Product.aspx?Item=N82E16817139020

Both are great quality PSUs.

You're concept on efficiency is incorrect. All of the above PSUs can deliver their rated power; i.e. 650W or 750W. You're looking efficiency from a PSU to PC component perspective and the correct way to look at it is from the wall outlet to the PSU. PSUs convert AC power from the wall outlet into DC power that is used in the PC. PSUs don't convert 100% of the AC power into DC power; there are power losses in the conversion process and heat is the most common loss. So if the above 650W PSU is supplying 650W of power to the PC at an 85% efficiency; it is actually drawing 747W from the wall. It still delivers the full rated power of the PSU, it just draws more than that from the wall.

 

[pratmodi]

A system running two GTX 550TI in two-way SLI requires a 650W PSU with at least 44A on the 12V rails and two 6-pin PCIe power connectors.

The Corsair Enthusiast Series TX750 V2 with 62A on the 12V rails and four 6+2 Pin PCIe power connectors is more than sufficient for your build and OCs.

The Corsair Enthusiast Series TX650 V2 with 53A on the 12V rails and two 6+2 Pin PCIe power connectors is also sufficient for your build and OCs: http://www.newegg.com/Product/Product.aspx?Item=N82E16817139020

Both are great quality PSUs.

You're concept on efficiency is incorrect. All of the above PSUs can deliver their rated power; i.e. 650W or 750W. You're looking efficiency from a PSU to PC component perspective and the correct way to look at it is from the wall outlet to the PSU. PSUs convert AC power from the wall outlet into DC power that is used in the PC. PSUs don't convert 100% of the AC power into DC power; there are power losses in the conversion process and heat is the most common loss. So if the above 650W PSU is supplying 650W of power to the PC at an 85% efficiency; it is actually drawing 747W from the wall. It still delivers the full rated power of the PSU, it just draws more than that from the wall.

Thanks very much ! Thnx for clearing the concept , Veteran

 

[pratmodi]

Best answer selected by pratmodi.

 

[Rugger]

YW - glad I could help - enjoy your new PSU!