Big Problem Not Sure Where To Post This Problem

[Bustedmac]

Hi, I was not sure where to put this one and hope i can find a way to fix this problem.

 

I got a free iMac G4 1.25 Ghz 17" from My cousin a few weeks ago he had it in the basement.

It was haveing a Problem with Kernal Panic basicly he got a new Mac and gave me this one i Formatted and Zeroed the Drive 2 times. I Installed 10.4.11 it was running 10.2.x and cleaned the Vram and Pram becouse the screen had lines going down it and was destorted plus it had that problem with the Kernal Panic. seems it worked out for 2 weeks or so. But now if i startup the system dose not get past the apple it gose blue and the lines come back. i tryed restarting cleaning Pram and Vram cleaned it up to 7 times before starting up the system seeing as to how you need to shutoff anf startup the system buy shutting down the computer to clean the Vram or only the Pram will be cleaned. So i had the system runing then i let it go to sleep it caused a Kernal Panic. I also tryed to install a game it installed but as soon as i did that the Screen went bad again when i tryed to start the game. I seen the lines and destortion again. now it's not so good the lines keep comeing back. I was wondering if any one could tell me what woud be causeing that. I looked at a few priced to replace the Logic board in this system but it's about $350.00 and thats more than the system is worth. im open to ideas on how to fix this problem. but not wiling to spend the $350.00 do it. I mave seen used iMac G5 2 Ghz Systems for about $599.00 better than spending the money to fix this iMac. I do have a 1.25 Ghz Mac Mini so im not going to be without a computer becouse of this problem. I would be willing to Buy a Logic Board for $100 or so to Fix This iMac Myself. it seems the iMac passed all test the Video Ram says it's good the Ram says it's good and the Drive seems to have no problems so im not sure if it's something Hardware related or not. Please give me some input if you can any info on what woud cause this problem.

Thanks for takeing the time to reading this and thanks for your help.