Hi all-

Without boring you with the details, I have been having some issues with my system. I'm trying to narrow down the possiblities.

I have a Palit GTX 560ti GPU.

In the course of searching through various forums, I've discovered that among the recommended specs for the 560ti is a PSU with minimum 31A 12v rail.

My PSU: Antec Earthwatts EA750. Among the specs I find this tidbit: "Output +3.3V@25A, +5V@25A, +12V1@25A, +12V2@25A, +12V3@25A, 12V4@25A, -12V@0.5A, +5Vsb@3A"

So, my EE knowledge is pretty limited. Does this mean that I have 100A on the 12v rail, or just 25?

As you may guess I'm wondering if, despite its 750w rating, this PSU could be insufficient for the card.

Thanks

That specification should mean 25W.

If you buy a new PSU, look for a single-rail PSU -- then there is no problem due to "small rails". Also, look for it to be rated for full power at 40C or higher. The reason folks use "big" PSUs, say 850W, is to allow for the fact that many PSUs are rated at room-temperature (not 40C+). So, they really don't provide full power once the computer comes to full temperature. Sometimes the falloff is dramatic -- say 750W down to 450W in one recent PSU test.

FWIW. The one in my signature runs my entire system (which is beefy) -- Crossfire, 5 hard drives, overclocked. Its rated at 650W at 50C. AMD/ATI says that's enough to Crossfire two HD5870, for example. My system draws roughly 600W from the wall when CPU and GPUs are 100 percent (that should mean the PSU is only operating at about 500W). I bought it for $59 after rebates. Just got a second one on sale for my upcoming Bulldozer system. Not on sale its $90 -- and one might find something better on sale for $90 (or one might not). PSU branded XFX, made by Seasonic (a big name in quality PSUs).

Thanks for that, Allen. That's what I suspected.

I see on Nvidia forums that a lot of people are having stability problems when they push their 560ti's hard. I suspect that insufficient amps is a common problem, as I only unearthed the 31A reqirement after a lot of reading. It's not exactly headlined in the card specs.

Cheers