0
Score
paulrapid
13
Asked
Blue screen on iMac G5 after replacing logic board
17 inch screen
2.0 GHz
Purchased from Apple July 2005
1 GB RAM
SuperDrive works
160 GB hard drive
Upon booting it goes to a "blue screen." I swapped the HD for a new one and same problem, so I assume the drive is good. My research indicates a bad logic board, but what do I know.
It will boot from the install disk and allow me to do a complete reinstall, but that does not solve the problem. I can boot from an external hard drive but it still goes to the "blue screen."
The original logic board was replaced by Apple in '06, under warranty. They would not do it again since my AppleCare warranty has expired.
1
Score
David Iwanicki
2.8k
Answered
Try booting from internal hard drive in verbose mode - "apple-v" held down at power on. It may help determine what is causing the boot failure. My suspicion is a graphics system failure, since the install disc is not going to kick in higher graphics modes. The blue screen occurs when the boot transitions from lower level processes to start higher level processes, kick in graphics modes, preferences, etc...
Also, look at the logic board for indications of swollen or burst capacitors.
Unfortunately, it was common for the reworked boards to still fail, even after the capacitor issue was identified (because only the failed caps were replaced on the original reworks, known suspect caps were left on the board if they were still working - causing the board to fail again when they burst later.)