May 11, 2009
Building a system with a P6t Deluxe v2, 920, and a GXT 275. Will a Antec Signature 650 be enough if I plan on overclocking, and might one day have get a second 275, or would the 850 be safer?
Antec Signature 650 should run all that comfortably. OC'ing both GTX 275s and your CPU might push you over 500watts DC power required.
You could look at the Antec TPQ-850, 80 PLUS Bronze and Modular cables for only $10 more a/r @ NewEgg.

The Corsair 650TX is about 1/2 the price of the Antec Signature 650 and has a little more +12V power. 750TX will also save you $70 with a nice bump up on that all important +12V rail to 60Amps.


Dec 24, 2008
Corsair 750tx would be my choice: http://www.newegg.com/Product/Product.aspx?Item=N82E16817139006&Tpk=corsair%20750tx
PC Power & Cooling Silencer: http://www.newegg.com/Product/Product.aspx?Item=N82E16817341011

Antec Signature is one of the best PSU's on the market, but it will be running at high load if you decide to SLI, so a 750w PSU would be my pick. If you won't SLI, then the Signature is a great choice. If you want to spend the cash for the 850w Signature, then that is even better, but its tough to justify spending that much money on a PSU I think. Those two options above would do fine for you.

Overclocking adds little to the power requirement. A second GTX275 adds plenty. For starters, you will need 4 pci-e psu connectors, the Antec 650 only has two. A good quality psu might work ok using molex to pci-e adapters(which should be inclused with the vga catd), but it is safer to get a psu designed for such use.

The corsair 750 and PC P&C 750 recommended by xthekidx are very good options.

For a 600w unit, look at the corsair 650, or the PC P&C silencer610 units which will power any single vga card out there today. The GTX275 is a very capable card, and you may not want to upgrade it for a while. When you do, the newer 40nm parts should be out near the end of the year, and a strong single card solution will be available to you.