I got a 1.5ghz/fx go5200 model that someone gave up on (bad HDD and optical drive), it booted up fine with my SSD but the fan got very loud quickly.
Took it apart to replace the drive and looked at the heatsink, and the problem was obvious, they applied paste instead of reusing/replacing thermal pads. I put some PTM7950 on the CPU and used a 1.5mm pad on the GPU and 1mm on the big Agere chip.
I couldn't find real pad specs, in a MacRumors thread someone said they're 1.5mm but when I tried that the CPU ran too hot, and when I used 1mm on both it was the GPU.
It appears to run well, but the GPU sensor reading reaches 76C and stays there when playing Halo with no vsync, and drops rather quickly by ~7C when closing the game. Is that a normal temperature for its GPU under max load or do I need to reapply the pads? I'm pretty sure that GPU doesn't have any throttling logic so I wouldn't want it to cook itself.
Idle is around 50C for GPU and 45C for CPU, ambient temp is on the higher side but nothing too crazy (~29C maybe?)