These are the two I am thinking about getting. Also, how hard is it to overclock a GPU? How much gain can you expect by doing it? If it isn't that much of a gain, I will just get a "Superclocked" version as shown above. However if it is a nice gain I may get the original 560/570 and overclock it myself if it isn't too difficult. After all, I am already overclocking my processor, just never have done it to a GPU before.
OCing a video card is easier than OCing a processor like 100x.
The 570 is better than the 560 TI. It isn't even really a competition. The 570 blows away the 560 TI with the same level of OCing on both. I would think it would be difficult to even OC the 560 TI enough to equal the basic 570 with no OCing.
The level you can OC at depends a lot on your cooling setup, though, and you haven't yet described that.
OCing a video card you can expect about the same gains as OCing a processor. It really depends on whether or not your video card is bottlenecking anything, though. If you are playing some game from 2002 and getting 100+ FPS, going up to 120FPS isn't going to be a change you can "feel".
If you are playing Skyrim with ultra settings and 4x AA then you would be able to notice more the OCing of the video card (although Skyrim also bottlenecks the processor on high settings too so if your processor is barely cutting it you could potentially not notice a lot of gains by OCing the video card).
Well, I would be using a 2500K on an Extreme4 mobo in a HAF X case. CPU temperatures wont be an issue as I am using the Noctua NH-D14 (I think?) cooler, but how well do the stock coolers work on GPU's?
The ambient temperature of my room sits at around 20 degrees. (Celcius)
As I read the HAF X has very good air flow, so I should be good to that end. If overclocking a GPU is easy, I should be able to do it with my setup, I was just wondering how easy/difficult it was. Also, does anyone have any experience with the EVGA overclocking tool, EVGA Precision?
You should just be able to use the regular NVIDIA software that installs with the graphics card.
ATI has a thing called the Catalyst Control Center that has a thing called ATI Overdrive built right into it where you just move some slider bars and hit OK and OCing is that simple.
I am pretty sure NVIDIA comes with their own "completely different" version that does the exact same thing, but I don't know off the top of my head what its called. I have seen someone use such a thing with their GTX 470 and it was no harder. I am assuming that what they used was just the Nvidia built in thing too.
Anyway, its not hard, don't worry too much about it.
The HAF X should be fine with OCing 1 video card.
The biggest problems with OCing are related to 1) Drivers and 2) Physical distance between the cards in 2+ video card setups. Both of those don't really apply here.