Chosen Solution
There is a single straight vertical line of what looks like dead pixels covering the height of my display. The error persists throughout the BIOS & start-up screens, does NOT show on external displays, and doesn’t seem to change at all with pressure applied to the screen. I have tried updating, downgrading, and DDU fresh install of GPU drivers and all other reasonable drivers on my device with no improvement. I have also tried pressing gently-firmly on the top/bottom/rear of my display with no change. It’s just out of warranty so a free repair/replacement is out of the question - so here I am. Open to suggestions for software fixes although I’m pretty convinced it’s hardware, no idea where to begin to try and repair/replace the screen or cables or anything however.
@gohw going by your description of the line etc., this appears to be a TAB error. It cannot be fixed. Sometimes you can make that line go away by pressing on the edge of the screen where the line is. There is really no permanent fix for it. Replacing the screen will be the only option at this time