Hey, I have got a Sapphire HD4850 toxic and its fan (zalman vf-900-cu) is always spinning with the same speed (independant of temperature or clock). It is very noisy. As a result I flashed the bios (RBE and winflash) of that graphic card with different fan settings. For example I set "Tmin" to 60°C and "Duty cycle min" to 0. I tried several settings but the fan speed didn't change after flashing. It runs always with about 1800rpm. I don't know where my mistake is or if it is even possible to reduce the fanspeed of that card with a bios flash. On request I can post some further information and pictures. I am thankful about every help.