I noticed that you said that you like to run GPU coolers without a fan controller, does this graphics card control fan speed based on GPU temperature? or is it 100% all the time?
In the stock form, yes the nvidia 8800 cards control their fans RPM based on the GPU temperature. This is only with the stock cooler. The after market coolers use a separate 3-pin power connection rather than the fan header on the VGA card itself.
is that the dark green graph on the upper one that just says HC92
The HC92 is the cooler plugged in to the 3-pin header on the mother board, where as the others have the controller connected. The reason I took the non-controller reading was to see if the controller did in fact put out full power. With a lot of controllers you will find that they will not put out 100%.
Also, what GPU cooler are you running? Looks like the Zalman but what model? (you referenced the CPU cooler when talking about the noise level of the HC92 on low)