DMG Classic GameBoy screen glitching problem

[Pap-Corp]

hey guys, looking for some help:
i bought a new shell for one of my old DMG gameboy and started transfering the internals to the new shell. when i turn on the console this is what i get on screen:
[youtube][/youtube]

The system was taken apart and laying in parts for a long time (like 3-5 years in a closed box. but at the time i took it apart it was working for sure (just the shell was super damaged, scratched and painted a milion times0 and i never had ny problems with the this unit in the past.

If i go full contrast the screen goes all black like normal but on normal settings i see some weird glitching (you can't really see it well on the video cause of the shell (i might make 2nd video if anybody wants). Those are not the vertical lines that represent bad connection (cause the screen can go all black) but weird glitches all around the screen. What it looks like on the screen is that wen the NINTNEDO logo shows the glitch goes on, and after the game loads and some things in game happen the screen glitches around it's definietly getting some data just not showing it correctly.
I have the speaker cut off at the moment and nothing bridged there (if that might be the case? will try with speaker soldered on later).

Any ideas guys? I wanna fix as much as possible without buying new internals, i can provide any photos if needed.

 

[slaphappygamer]

I looked into this a while ago and found many videos such as

 

[OfficialFBomb]

Even though it does not look like it i would def try the lines fix first. I had two i fixed this way, even thought they did not present the same way yours does. And yes a second video showing the issue with a game running would be best.

 

[Pap-Corp]

okay, will try this today.
but what is worrying me is the fact that i dont even see the game at all (i dont have a game with missing lines i just got the lines randomly showing). that is why i didnt even thought about this trick, which im familiar with
im gonna get back to ya after that

 

[Dark_Knight_DA]

It could be either this or the ribbon cable has not been seated properly. I would advice carefully re-opening the unit and ensure that the ribbon cable is fully attached and if no progress is made, then follow the advice of OfficialFBomb