Hello. We are trying to work out what is wrong with an imac G5 with isight. The problem is this pattern all over the screen. I have opened it and looked at the logic board and all the caps are fine. None are even bulging. I replaced the thermal paste on the GPY and had a look round for anything obvious but nothing is jumping out at me. When the system is turned on it waits on the apple logo for a while before the fans kick in and it eventually fades to black. It will start in safe mode. I have tried to run hardware diagnostic from the install CD but the screen displays a lot of odd colours before fading to black again. However when I tried and made a video it did this? Edit. Just tried again to boot the hardware diagnostic. This time the screen is split white and pink on the right. Which fades in and out, looks kind of like pink clouds. My assumption is that the GPU is past its prime and a new logic board would be the only way to go. If anyone could offer any advice I would be very grateful. Laurie.