Our 5 year old Imac started having thatched squares on the screen after a few minutes being on. Doing some research showed it was a common problem on 5 year old G5's. I inspected the capacitors but didn't find any bulged ones.
Trying to isolate the problem area with a combination of cold spray on individual components and heat, I ran it with the back cover off. The cold spray didn't find anything but the G5 has been running fine for the last 3 days this way. If I put the cover back on, the problem re-appears. So, looks like a heat issue. I'll be using it this way until I can, if ever, find the exact spot or component that's causing the problem but I wonder how many G5's have been scrapped when this is a simple solution. I'll make a small set of stands or legs out of wood so it safer and the speakers resonate more but otherwise, even if it is an older G5, it's good enough for surfing the net and running other tasks..
Trying to isolate the problem area with a combination of cold spray on individual components and heat, I ran it with the back cover off. The cold spray didn't find anything but the G5 has been running fine for the last 3 days this way. If I put the cover back on, the problem re-appears. So, looks like a heat issue. I'll be using it this way until I can, if ever, find the exact spot or component that's causing the problem but I wonder how many G5's have been scrapped when this is a simple solution. I'll make a small set of stands or legs out of wood so it safer and the speakers resonate more but otherwise, even if it is an older G5, it's good enough for surfing the net and running other tasks..