Thanks for the input Brian. My plan was to mount the esc bottom side directly to my CRT chassis via CPU paste. Not sure if you've seen my CRT project thread but there's pics there showing the plan. I also don't want fans. Fans are band-aids. Use them only if you have a boo boo is my philosphy. But from reading above, it read like there was an issue with how the Quark conducted heat from the innards to it's own case. If this is the problem, my external chassis sink plan wouldn't have helped. I will be running a Neu 1515/2.5d on 5s. Think I am ok?