3 
5 White screen - Pink vertical lines - White screen
Ref: iMac, 20-inch, 2.66GHz Intel Core 2 Duo - experienced white screen. I followed corrective procedures given on multiple web pages. At first, successful but then appeared thin vertical pink and green lines. Continued with procedures, and succeeded at returning to white screen. Does this mean the hard drive should be replaced?
Update (12/03/2017)
Update: I ordered a logic board from ifixit and followed the guide to replace the logic board -
iMac Intel 20" EMC 2133 und 2210 - Austausch der Hauptplatine
I believe I completed all steps correctly, except at Step 10, I did not mark the inverter cables because the instructions indicated them to be interchangeable, however the comments indicated otherwise.
I reassembled all and pressed the power button, but got only Black Screen and Beeping at intervals of about 2 - 3 seconds. I went back and tried all combinations of connecting the inverter cables, and still got Black Screen & Beep.
Please advise. Please...
Ist dies eine gute Frage?
970 
4 Kommentare
What were your procedures??
A white screen with pink or other colored lines is a video issue not a hard drive issue. I would focus on reviewing the display logic.
As for testing to isolate out whats bad: I would connect an external monitor to see if the image is clear on it Vs the internal. If its not, then the GPU is bad. If its good then you either have a LVDS cable issue or the internal display is having issues.
von Dan
One for example, from: https://macreports.com/mac/
To clarify - the problem is currently white screen, no vertical lines. Previously I had white screen and reinstalled the OS, and solved it. Then more recently, the vertical lines developed, over normal background. So trying the steps again, it produced only white screen. So now it's just white screen only. Thanks for the tips. I don't know how to connect an external monitor, or even where to find one but I'll try to figure it out.
von mchlgrblsk
On the back side of your system you have a mini-DVI connector so you can plug in a mini-DVI to HDMI adapter and a standard HDMI cable to plug in your TV or external display.
von Dan
Ok, I bought a mini-DVI to HDMI adaptor, connected it to my TV, and white screen appears on the TV. So that means the hard drive is bad, correct? And if I want to keep using the iMac, I should replace it. Thanks for the input.
von mchlgrblsk