I'm tired of the crazy heat that my GTX 480 produces (my computer increases my 10x10 room temps by a whopping 8 degrees). That's right, whopping.
I'm going to be building what is going to primarily be a workstation. I'll be using either an i5 3570k or an i7 3770k in this build, and would like a COOL graphics card to go along with it. By cool, I don't mean a card with an aftermarket cooler that'll keep the card at low temps. I'm looking for low heat output. Right now my thoughts are a GTX 670 (a 660 may be a good candidate as well). I play games, but I'm not an FPS junkie. As long as I can stay near 60 FPS on medium settings, then I don't really care. I'd *prefer* an Nvidia card, but I'm definitely open to AMD alternatives.
Would Keplar be a good choice, or should I be looking at something else?
Generally speaking, the lower performance the card has and the less power it draws, the less heat it will generate. Therefore, a Radeon HD 6450 produces less heat than a Radeon HD 6970, but due to the smaller heatsink on a Radeon HD 6450, it's operating temperature will not be much lower than the Radeon HD 6970 with it's massive heatsink in comparison.
The Radeon HD 7750 is an example of a card capable of providing great performance based on it's low maximum power consumption of about 43w. It's performance however, does not compare to the GTX 670 which has a max power consumption of 162w.
You should probably take a look at the following GT 670 review which includes power consumption, performance per watt and performance per $ charts to help you make a decision.