Yes, thanks. Many people at ACP have different cameras etc.. so cross-posted here...
For the record:
This was very bad because it started intermittently with a bad fan then overheating. I think the fan is designed to keep the board dry... will tear apart this AM and see if I can see any problems on the board. Others have had corrosion that jumps contacts and was cured with cleaning... I can always hope. I had the same thing with my SBIG 8300. Had to replace 3 times!
I learned that there is a spray that waterproofs such boards.
Bad for me as a lot of humidity near San Fran.
Case is open with ZWO. I have a friend with a Morovian version with the same SONY chip.... twice the price.