GeForce 6800 fan speed control; nvclock segmentation fault

Question

I recently did an update on my Ubuntu 11.04. Unfortunately I can't remember what was updated, but I am sure there were some core things.
Anyway, before that update I could change the fan speed, due it's heavy loudness, with an application called nvclock.
When I try to use it now with:
nvclock -f -F 70

I only get following reply:
Segmentation fault

So how can I get it back working, because it's really annoying loud

Answer 1

With GF6800 on Ubuntu 10.04, i have the same problem. My workaround to change GPU fan speed is:

sudo gedit /etc/X11/xorg.conf

in section "Device" add

Option       "Coolbits" "5"

Restart the PC. Then you can control fan speed with this command:

nvidia-settings -a [gpu:0]/GPUFanControlState=1

and then:

nvidia-settings -a [fan:0]/GPUCurrentFanSpeed=30

where 30 is a number from 1 to 100 % of fan speed.

You can set that two commands in Startup Applications to run at boot, remember it if your GPU overheates.

Cheers