Sorry, the CM could only modify your post and not answer it! Let me explain what the other have passed up!
Dust causes added paths for electrons, allowing ELECTRICAL PARTS to CONDUCT when they shouldn't.
The Dust may have been laying on the board, because NO AIR was moving in it! It is fried as a result of bringing out of "moth Balls" and not cleaning it first!
Does it smell like a fried electrical part? IF no, then do this before it is too late:
Unplug it, and blow it out with a can of COMPRESSED AIR!
If it does smell like it has a BURNT smell, it is fried!
You can't fix stupid! - Ron White