With cgminer 2.0.2, even with --gpu-fan 50-100 (for restricting fan speed between 50 and 100%), the fan speed is set to 0% shortly after startup on all GPUs (I have 5 on the rig exhibiting the pb, one being without fan associated : a 5970). So I can confirm the problem reported in the thread referenced above.
The fan speed up only when hitting the target temperature and the rate at which the temperature climb can prevent cgminer from speeding the fan early enough and some GPU can fail.
Other quirks :
- my 5970 doesn't seem to accept the fan speed targets and only accelerates or slows down (speed set to 100% only increments the speed, doesn't set it to 100) the other cards don't have this problem.
- Another quirk is that for the same 5970 card the inability to set the speed right away generates a yo-yo effect : the fan speed and temperature oscillates quite widely (30 to 70% and 15-20°C range).