I have been having the same problem for quite some time, and have also yet to figure out a solution.
The computer can be sitting idle for some time, yet the GPU temperature hovers around 72C with the fan only at 282RPM. Once opening any small graphics file, or doing something more than simple word processing, causes the temp to rise rapidly to roughly 89C before the fan kicks in at full speed, and very loud. The temp gets to about 94C before it starts to cool down to roughly 85C, the fan stops, then as the temp rises again to 89C, the fan kicks in again at full speed. This is very frustrating and annoying. I have tried uninstalling and reinstalling the software, without success.
Have you solved the problem yet?