New to StackExchange/Ask Different. Been a lurker for a long time, this is my first question/discussion. I hope somebody might point me in the right direction.
I was recently given a couple old iMacs that were going to be thrown away by a family member. The others all work fine after a format and memory upgrade. However, one of them does not. It is a 17" iMac Intel Core Duo 1.83Ghz. Here is a link to the exact model info.
On bootup, I get the normal Apple start sound, but the screen only displays multi-colored lines. Here is a picture. I pulled the plastic bezel off, and tried removing the screen panel, and reseating the screen cable. I also removed and reseated the memory, and tried resetting NVRAM, all with no change. I don't need to worry about losing any data on this system, I will format it and clean install OSX when I fix the screen.
What should I try next to figure out what is causing the screen issue?
Thanks in advance!