I was bit surprised when after modyfing cubes per youtube video (anyone did put heatsink on all DC converters?) and applying new thermal paste I managed to get my problematic dies to work at full spead. I had 2 that would run at 125mhz max. now they running at full 300mhz (didnt tried more).
and was shocked how dried up thermal paste was on some cubes:/
btw anyone ever tried to put some water cooling?

This is a very interesting observation. Have others had a similar experience? Is there a good video out there showing how to do this? I saw one video that wasn't bad, but I would love to have a close up view of how to do this. If it really makes that big of a difference then it certainly sounds like something I would like to do also.