Picture has narrowed vertically to 1/3 of screen

It's actually the panel that's bad, not the board, one of your clock lines are shorted but it can be fixed with a piece of scotch tape by masking off the correct clock line, there should be 8 of them and it will give a decent picture just using 7, there are some youtube vids that describe how to find the pin to block if you want to dig into it.

Vertical lines on Samsung LED TV PlayItHub Largest Videos Hub

Check on another external monitor, if the picture is ok there, eliminate a faulty graphics chip
If picture is still poor, Graphics chip is faulty

You are now left with the issue of it being the VGA cable from the mobo to the screen, or a faulty screen. It may be that you just need to have the connections checked, but also may point to a replacement screen or Cable being needed

Check solder on the vertical output or change it. Dont know # but look for IC screew on heat sink with about 7 to 14 pins.

you'll need a new panel, or a new TV, sorry

Your vertical IC needs to be resoldered and change the capacitors in that immediate area. Always check for bad grounds [cracked rings around the pins, look real close to find] on any and all ICS mounted on heatsinks. And large resistors as well.

Bad solder connection in the horizontal pincussion circuit.have someone resolder.God luck.4tune

Hello Adam...

Most likely a bad formatter board, which plugs in vertically on the signal board.

1 it is due to electrolytic capacitor defective in vrtical output stage. 2 loose contact in vertical. 3 fault due to feedback ckt in v/stage. as per schematic diagram is concern check www.serviceinfo.com

If the line goes across the screen you have a loose solder joint on the vertical output IC. I've seen this happen many times in Zeniths and a lot of other sets. If the IC is not loose then there is a loose solder joint somewhere else in the vertical circuit. These IC's are 10 - 13 pin chips that operate the vertical deflection on your set. I feel like a drop of solder in the right place will fix it! Stargazer