Dead Atari 400 - solder splatter?

[Chupperson]

I'm trying to bring back a dead Atari 400. Right now when you turn it on it just sends a signal that lacks sync and looks like one white line scrolling across the screen. It has the Tiny Tek 48K expansion.

It also has some really bizarre solder splatter on the underside of the CPU board, under the logic chips on the edge of the board. I can't imagine this came out of the factory this way, but I'm at a loss as to how it could have gotten there. Something overheating and causing that large solder path to leak out somehow is my best guess.

 

I'm going to clean it up and continue cleaning the boards, but is there anything in particular to look for while trying to get it to work?

[Gunstar]

The only time I have ever seen something like that, was in school when I was taking electronics. My soldering lab partner was attempting to get a drop of solder onto the soldering iron tip for some reason, right over the motherboard we were practicing on and the solder dripped and splashed all over the board like that. He cleaned it up with the soldering iron and a solder sucker.

Edited September 11, 2017 by Gunstar

[Keatah]

That'd come from the factory. Seen it all before. You can continuity-check it for bonus points. And I bet what (if any) is really shorted, it's supposed to BE shorted.

 

So, clean it up and carry on.