Pulling out the TES 1350A Sound Level Meter we find ourselves quickly yelling into the top of it to see how loud we can be.
After five minutes of that we get a bit more serious and place the device two CM away from the fan on the card to find the maximum noise level of the card when idle (2D mode) and in load (3D mode).
Fortunately noise levels stay strong. No doubt if you wanted the card to run cooler you could force the fan to run a little louder. 75c, though, isn't a number you have to really be worried about all that much.