Don't overlook the fact that you can delete all of your ati software (besides the actual driver) and run ATI tray tools and it will give the same fan controls and overclocking utils and all the other good stuff that came with the ati control centers.
I've been able to keep my unlocked x850pro that used to run in the 65c-70c's under full load to 45c-50c's with a ATI silencer and a nice progressive C's to fan % ratios.
Start at 32C and make it 0%fan usage
33C = 10%
It will idle around 33 and max around 45-50 depending on what you're doing.