Side Effects for the Radeon HD 2600 XT Firmware Update

If the ATI Radeon HD 2600 XT Firmware Update fixed the freezing issue experienced by many Mac Pro owners, it seems to have unexpected side effect.
It seems than the graphic card can not enter into lower power consumption mode as it use to be when only working in 2D. As a consequence, the GPU fan spins at full speed generating unexpected noise.
For information the GeForce 8800 GT is really silent and never generate noise which will be higher than the one created by the entire cooling system of the Mac Pro...