Boot loop with weird lines on screen

Hey everyone.

I have an iPad Pro that my brother gave to me (he bought the new one) and have been using it happily for over a year.

I'll say straight up that this has not been dropped, knocked or gotten wet. I am very anal about my gadgets. I don't damage things.

Suddenly the other night it froze while my wife was using a planning app (5D something) and the whole screen was green and magenta blocks and lines.

I did a force reboot of it and now it's stuck in some kind of boot loop.

It goes like this:

The iPad goes to the normal Apple logo screen. There are no glitches or artifacts on this screen. It looks as normal. It goes to the black screen and back to this over and over.

If I hold the sleep and home buttons down it starts to do what you would expect when doing this and resets and then goes to the apple logo again except this time you get the loading line under the logo for a second before that disappears and the whole screen gets covered in lines and blocks. These can be blue, magenta, green or black (so far, maybe it can do other colours).

I've forced it into recovery mode using iTunes and I've let the battery go completely flat.

I repair things regularly but have no experience of Apple devices, and from what exp I have had I've found them far too much trouble to bother with but I got this for nothing and I actually like it.

Chances are it's totally borked but if anyone has seen this or has any idea how to fix it I'd love to try. Seems to me like it's not a bad connection with the screen because the initial Apple logo screen and the screen you see when the iPad needs charging all look fine.

Am loathe to take it to Apple as I'm sure the answer will either be "It's out of warranty so tough luck" or "Nothing can be done, buy a new one".

Very comfortable with opening things up and soldering etc. so happy to try that.

Thanks in advance.

Dave