I'm not using the control panel anymore, just RivaTuner.
I turned up the fan to 75%, and it's still relatively quiet. (That may be because I have a large window-fan, on low setting taking place of the case cover.
It seems as if RivaTuner only affects the fan mounted on
the graphics card, though, not the other case fans.
Also, I'm looking into overclocking my CPU, also. Not by a lot. It's 1.8GHz, I want to get it to maybe 2.5.
That seems like it'd be a bit more dangerous, though.