I have an HP desktop with nVidia GeFoorce 7100 video. Anything such as Fedora 15 or open SUSE trying to use the Nouveau drive either out and out kills my video or eventually caused everything to lock up. It may be great for tablets and netbooks but it isn't worth a shit for desktops!
WRT the graphs on page 6 of the test results, showing more frames per second with the proprietary driver, then the comment that it is 'interesting' that the Nouveau driver uses less of the CPU, well, this is exactly what you would expect, and is not a surprise at all, because the increased frames per second is directly the result of the increased usage of the CPU by the proprietary driver.
You totally stole my post. The driver is indeed the bottleneck there.
Interestingly, when using the NVIDIA driver its core temperature was higher than the Nouveau driver for the GeForce 8 series. For the GeForce 9 series, the core temperature was lower. This is quite odd that the NVIDIA driver produced a higher core temperature while being more power efficient, but perhaps there is a bug in the GeForce 8 series reverse-engineered thermal sensor code that is causing the core temperature to be lower than it actually is running.
Have you thought about monitoring fan speeds? The nvidia binary driver switches between different performance levels according to the gpu-load.
In many graphic cards bios a fan speed value is set for each performance level
(take a look at nvidia-settings powermizer).
The nouveau driver, like earlier stated, does not automatically switch between different performance levels.
Overall it would be much much more interesting to see, if it is possible to lower the power consumption of the nouveau driver.