GTX 260 in SLI, is corsair TX 650W enough?


Nov 26, 2008
Hi, I am thinking of buying a XFX 260 GTX to run in SLI, and am just wondering if the Corsair TX 650w power supply will have enough juice? According to the corsair website it has 54A on the single +12v rail.

I have checked with 'extreme power supply calculator' which says i need roughly 600w for my setup and will have enough amps on the rails. However, there were a load of settings that i left at recommended but didn't really i'm not sure if the wattage refers to peak, or average or whatever.

Basically, just wondering if people think this will be fine? Anyone have success using similar wattage?

I would be pretty leery on the 650W. What does the rest of your system look like?

One thing I am leery on is the TX650 has only 2 PCI-e connectors, you need 4. I think the TX 750 would give you enough juice and has 4 pci-e power connectors. I always hate using the molex to pci-e adapters. Just never seemed like a kosher idea. But I could be wrong. Then again you probably do have enough juice to run it on the 650, but I always error on teh side of caution.


Oct 9, 2006
It'll probably be enough, but you'll most likely be running at 90% load almost all the time. That could lower the life-span of the PSU. I'd go with no less than a 750watt PSU to keep it around 80% load or lower. I think 50-80% load is a sweet-spot for efficiency and life expectancy, but I'm not 100% sure on that ;)
I think i just don't like using the 2 molex to 1 pci-e adapters. I think it depends on what the rest of your system is.

I still think if you are running SLI 260's you should have a PSU that has 4 pci-e cables. And like Leo2kp says, you dont want to max out your power supply. Then again you also don't want to underutilize it.


That PSU calculator is pretty much a worst case scenario - as in everything running at full power at the same time. It's a recommended 600w PSU - not that your system will actually use 600W. "Recommended PSU Wattage"
And that recommended 600w PSU is probably an "average" PSU - not a high quality PSU.
I think you'd be OK to use the TX650 especially if you're not into extreme OC'ing (CPU & GPUs).

I did some quick looking and found a few power consumpion sections in reviews. They all basically say the 260 sucks about 40W less power than the 280. And looking at this review 2 280's in sli on this system at full loads sucks 746w - 80 for 2 260's that puts you at 666w full load.,2120-8.html

Granted this is an overclocked i7 system, but if you have an overclocked quad core you will hit about the same.

So depending on what the rest of your system is it could vary. If you have a dual core runing stock speeds, then YES the 650W is fine. If you running highly OCed dual core or oced quad core, then maybe it is wise to upgrade the PSU.


I think jay2tall estimates aren't far off. But just remember 666watts measured at the wall socket and with a PSU efficiency of of around 83% that means the PSU is providing about 552watts of actual DC power to the system. Or about 80% of the rated power of the 650TX (maybe 85% of the +12v rail worst case). With a 750TX that would be about 70% of the rated power.

My system.
Asus P5N-E SLI
GTX 260 C216 @ 700/1200
E8400 @ 4.0 with 1.3v
2x1g Ballistix Tracer's
2 x 160g HD's in Raid 0
1 x 160g daily backup drive
SB Audigy sound card
4 x 80mm LED fans
2 x 120mm LED fans
USB card reader
Keyboard , mouse , joystick
Corsair HX620 ( 50 amps )
Running Furmark and Orthos to simulate a gaming load, draws a max of 380 watts from the wall according to the Killawatt meter. At 83% efficiency that's roughly a 310 watt load on the psu.
The GTX260 uses about 150 watts, the only reservation's I'd have about adding a second card, is the lack of proper connectors.


Nov 26, 2008
Thanks for the input guys.

I erred on the side of caution before checking this post and went with the tx 750 (it was only 20 pound more). Although beginning to think that SLI might be a waste anyway (too much bottleneck) unless I overclock my cpu a hell of a lot. From what i've read i'll be lucky to get 3.2 out of the 9950 phenom (Black Edition, so unlocked multiplier).

My system:

Asus - m3h-hd/hdmi motherboard (nvidia 750a)
9950 phenom Black Edition (2.6 stock)
4 x 1 GB of Corsair 1066 pc8500
GTX 260
Trust PCI 7600 Sound card
1 x 190 GB SATA hard drive
1 x IDE DVD writer
3 x 120mm fans
1x 140mm fan
Keyboard, mouse