If I change the fan speed on the video card using the manual fan control on the catalyst manager will it fluctuate when the card gets really hot. What I mean is that when it is on default there is an automatic fan speed that will fluctuate the fan depending on how hot it gets. Will this happens if I manually change the fan speed or will it stay on the percentage that I set?
If you manually set the fan speed it will not fluctuate. Why do you want to manually change this? Are you overclocking? I've used ATI Tray Tools in the past to change my fan profile. This way you can increase the fan speed at certain temps to keep it cool yet quiet when not gaming.