After some distractions over the weekend, I finally have some news to report. Using the new PLL formula
sysclk = (refclk*fbdiv)/(prediv*2^(postdiv-1))
I was able to lower the sysclk to 100MHz, where the chips finally ran at a temp that did not burn my fingers when
touching them (infrared thermometer is on the way). I remember reading somewhere in this thread that chips
could be run at 200MHz without cooling, is that still true? Or does that refer to running them at idle (not under load)?
As a side note: the minimum fb_div appears to be 100. Anything lower would not PLL lock.