I would have been here earlier but I was watching a 100-minute expose on Babylon 5. ( https://www.youtube.com/watch?v=-FfKOubWE14 )
Welcome to the Pentium-Pro master race!
Ironically, those thermal pads often worked better than typical heat sink compound (of the time). Tolerances for heatsinks were very loose by today's standards. The pads were often better than goop until the pentium 3 /athalon era when they flipped the die to allow direct exposure.
I also want to echo @debs3759's request for a bios dump, boot images, and proper board pictures.
It is a mistake to think you can solve any major problems just with potatoes.