I removed the original crap thermal paste. i applied Clear nail polish around the APU so the liquid metal doesn't fry it. Then applied liquid metal on the the APU. So far
PlayStation 4 Turns On Then Back Off Repair - iFixit Repair Guide
PS4 Blue Light of Death - APU reball from begin to end - YouTube
Replacement APU GPU CXD90026AG IC Chip For Sony PS4 CUH-1100 889044060085 | eBay