emac G4 display flicker etc

[malachy]

Hi, I have an emac g4 that has a number of problems, It is a 1.25gz. Sometimes it will boot to a blue, blank screen, on holding down the alt key I see the boot drive and I can start up (10.4os) but will go to the blue screen again. When it does start up properly, which it does for no apparent reason, there are little dash shaped spots on the screen and a flashing horizontal flicker. I ran fsck and disk utility and installed a fresh version of 10.4 to no avail. I do not have the original disks so cannot run hardware test. The computer falls under the Apple emac screen repair but they will not accept it because it is out of the three year time limit, very frustrating and unfair. I read about an IVAD cable that can be replaced to repair the problem but am not sure if it is relevant to this problem. I would be very grateful for any ideas, thanking you in advance,
Connor