Comment # 116 on bug 66963 from Alex Deucher

(In reply to comment #115)
> (In reply to comment #114)
> > 
> > What sort of issue are you having?  blank screen?  currupt image?  GPU hang?
> 
> Screen goes to powersave when booted with dpm=1.  Still able to ssh in, but
> seems frozen from keyboard.

Does disabling any of the dpm features as per comment 94 help?