Re: How to set the minimum clock speed in adpative mode?
The problem you have is quite common. Modern, over-engineered desktop environment and nvidia card in low power state don't mix well.
IIRC you can't do exactly what you'd like to do (i.e. impose a min freq). What should work is to force max performance mode and at the same time underclock. Then it should stay at the frequency you underclock it to and you might get reasonable heat/power consumption and reasonable performance. Of course it won't be adaptive any more..