So I got a good overclock out of my GTX 570, and decided to keep the stock settings as a 2d profile, and the 3d settings as the overclock.
For some reason, when I am in 2D mode, the clock speeds will randomly fluctuate between my stock settings and EXTREMELY low clock speeds. I don't notice any thing bad about it happening, I can still browse the internet fine and stuff. But I want to know why it keeps downclocking even though I specifically have the stock settings set for the 2d profile, and the overclock settings for 3d. By the way, when I'm in 3d mode, the clocks never change. It only happens in 2d mode.
When you're in 2D mode, you don't use the GPU all that much - you're just touching it. For that reason the GPU clocks drop down to VERY little (the VRAM clock should do the same) so save energy and limitd the heat transfer. It's completely normal, and actually a good touch to keep your GPU saved from useless heat and clock speeds.
Yup, IIRC, this was the infamous bug that AMD drivers suffered under not too long ago--having *any* 2D type video window open would force the card to 2D clocks, even with a game open. That meant if you had paused a Youtube video or left a DVD window open, you'd get no FPS in a game you launch. The bug was that the 2D video had forced the clock to a 2D setting and it had a higher priority over a game, so 3D mode couldn't kick in.
What these two said, but why overclock a GTX570?
Why not? I just received my EVGA GTX 570 SC in the mail late yesterady and it is stock at 797 MHz and I'm wondering how far I can safely push it.
It idles at 40 C with fan on auto (40%), but if I push the fan up to 60%, it idles at 30 C. Haven't had a chance to stress test yet (coming tonight!).
See dude, some of us likes to see what their hardware is capable of. I, for example, overclock and stress my hardware to where it will go (sometimes even unstably) before I settle on an average use. For example, my GTX460 reached 1025MHz before I dropped it back to the 850MHz I run it at now (MSI Cyclone card). It's just what we like to do...
Oh and with regards to how far you should be able to push the GTX570, I'd say 900MHz stable with decent heat should be achievable, depending on the chip of course. I'm not very familiar with the EVGA coolers, but if they're anything as good as most other coolers on the chips, it should keep the GPU cool enough. As it comes with a factory OC of 797MHz (from 732MHz, and they call it a SuperClock version, fail), I think it will go much higher than that. It should be able to go about 825MHz with stock voltage, and after that you'll need to up the core voltage to avoid crashing/freezing in games. Also, when you stress it, try not to use FurMark, I've heard some bad rumors about it's burn-in tests. Appearantely it wears your GPU prematurely, and that, you don't want.
Be aware that the stock 4+1 phase power system on GTX 570 cards is inadequate for any kind of over-volting. Even a high overclock without over-volting can sometimes cause components on the power system to fail. There are threads on other sites with descriptions of what card and the situation that killed it, like one titled "Have you killed a 570?" The problem isn't heat, it's that the power components can't handle the extra juice required.
Some factory-overclocked 570s have better power systems and better coolers, like the ASUS DirectCU II, MSI Twin Frozr series, and Palit Sonic and Sonic Platinum. They either have a 5+1 or 6+2 power system, which is much better for overclocking and over-volting.
GP -- is your memory speed really that low? The stock speed should show up as 1900MHz in Afterburner. You're losing out on performance with the speed at 1250MHz.
Just stay below 1.1V and you should be okay, that being said don't just hammer teh voltage to max and stress test. I like to increase my Clock by 50Mhz or so at a time till I see artifacts then adjust my voltage to compensate, rinse and repeat and then back down voltage to as low as I can in small increments. So far on my cards I've reached stable temps and performance at 850/1900MHz @ 1063 mV with a custom fan profile to keep the cards under 75C. I could push further, but that amount of overclock on my cards is easily enough to handle any game I throw at it.