What a nice piece of kit. I've owned a lot of high performance cards over the years and this is very nice. The 3-slot design might be a pain if you can't afford to lose the slots but the cooling you get is amazing. I was previously running an Nvidia 8800 GTX: this 570 GTX runs significantly cooler under LOAD than the 8800 GTX ran IDLE. The only thing to note is that by default the speed of the fans is proportional to the clock-rate and NOT the temperature. You'll need to install the Asus Smart Doctor and switch it to enable "Smart Cooling", which allows you to set specific fan ratios (40%, 50% etc) for specific temperature ranges. That said, even with the fan running at the default speed and maxing it out with Folding@home I still didn't see anything above 65 degrees (this is in an Antec P183 case); with the Smart Cooling I never see temperatures above 56 degrees and that means a fan ratio of about 40-50%. That's just as well since setting the fan manually to 100% makes you realise how noisy the card COULD be.
I dislike noisy machines and buy silent or near-silent components: my CPU is passively cooled and I have 120mm silent fans etc. I chose this card because it offered amazing performance and was quieter and cooler in online reviews. Under max load, the noise from the case sitting under my desk is noticeable but not obtrusive enough to be an issue since I game with headphones on anyway. When idle or under moderate load, I can't even tell it's on.
If anyone is going to use this with the Antec P183 then note that you WILL have to remove the upper drive cage to accommodate the card; and you will NOT be able to fit it into the bottom-most PCIe x16 slot as the chamber-divider does not leave enough clearance.
I am running with an old Core 2 Quad Q6600 (stock speed @2.4GHz) with 8GB of RAM. I can run most games at highest settings at a res of 1920x1080.
For example, Crysis 2 at the max settings and with the additional DX11 bits enabled and also the high-res texture pack installed runs fine most of the time. Deus Ex: Human revolution also plays nicely at nearly the max settings: I suspect the bottleneck is not the GPU however since GPU-z on the secondary monitor does not indicate full GPU load.
Note, although you can overclock this card out of the box, the overclock is limited by the voltage range. You can push past that but you'll need to install Asus OSD software to be able to overclock this card beyond the default voltage range. I found that the software caused crashes with Deus Ex: Human Revolution and so I removed the OSD software. I was using the latest version as of Sept, 2011. Hopefully Asus or someone will patch it.