My 4870 was very quiet and in turn 60C+ at idle with load temps in the 90C+ range! This is a well ventilated case and reasonable ambient air. When you use the profile fan "fix" to cool it off, anything over 35% and it's annoying, the higher it goes, the more annoying it gets
My 260 on the other hand idles at 40C or so in the same case and room temps) and is barely noticeable with the fan at "Auto" (40%) Under the same full load it goes to 70C or so and the fan still isn't noticeable Oh BTW that's OC (so far) to 650
All in all the NV cards run cooler and quieter based on my personal experience
