It was in the 660's bag and in a closet. I had cleaned and re-applied arctic silver 5
Anyways, I loosened the heatsink a little and gave it one more go and I got a signal. I started in safe mode and had picture. I restarted to normal and it had signal. But about 20 seconds after windows opened I lost again.
So took it back= out, took off heatsink and cleaned thermal compound off and re-applied again and then put heatsink on but this time didnt tighten it down as much and to my surprise it now works.
Im assuming it was tightened to much and something was flexing and losin connection, or was overheating somehow due to overtighting?
Anyways its working now