minimariobros64
Level 1 (0 points)

Q: iMac G5 intermittent vertical lines on screen

Hi all! First post!

 

Ok so I have an iMac G5 1.8ghz with the vertical lines problem common with this model. But this is different... they come and go as they please.

 

When the lines are present the iMac will crash when booting up. If I tilt the iMac the lines change formation.

After around 30-60 minutes of failed boots, the lines go away and I can use the Mac normally.

The lines come back after the Mac has been off for 5-30 minutes. It's like they are only there when the Mac is below a certain temperature.

 

I've looked for a long time for a solution to this and haven't found one, so my only options are to go to a repair shop or ask here.

 

Any help much appreciated!

iMac, Mac OS X (10.4.11)

Posted on Feb 25, 2014 5:48 PM

by Allan Jones,Solvedanswer
Allan Jones Allan Jones
Level 8 (35,071 points)
iPad
A:

Welcome!

 

About all you can do yourself is see if the lines are due to bad video hardware on the logic board or simply a defective display.

 

If you have another monitor and the right cables and adapters,  you can attach the external monitir to the G5 and see if the lines persist. If they are NOT on the external, the problem is only with the display of the G5. If they persist to the external, you have a video hardware fault that is not worth fixing (new logic board).

 

For that matter, finding a working G5 replacement display will be neither easy nor cheap, as so many were required to repair defective ones. Several people here who could not/would not part with their defective G5s simply left the test external monitor attached and moved it in front of the G5 case. The computers remained in service that way.

Posted on Feb 25, 2014 8:08 PM

Close
minimariobros64

Q: iMac G5 intermittent vertical lines on screen

  • All replies
  • Helpful answers

  • by Allan Jones,Solvedanswer

    Allan Jones Allan Jones Feb 25, 2014 8:08 PM in response to minimariobros64
    Level 8 (35,071 points)
    iPad
    Feb 25, 2014 8:08 PM in response to minimariobros64

    Welcome!

     

    About all you can do yourself is see if the lines are due to bad video hardware on the logic board or simply a defective display.

     

    If you have another monitor and the right cables and adapters,  you can attach the external monitir to the G5 and see if the lines persist. If they are NOT on the external, the problem is only with the display of the G5. If they persist to the external, you have a video hardware fault that is not worth fixing (new logic board).

     

    For that matter, finding a working G5 replacement display will be neither easy nor cheap, as so many were required to repair defective ones. Several people here who could not/would not part with their defective G5s simply left the test external monitor attached and moved it in front of the G5 case. The computers remained in service that way.

  • by minimariobros64,Helpful

    minimariobros64 minimariobros64 Feb 26, 2014 8:27 AM in response to minimariobros64
    Level 1 (0 points)
    Feb 26, 2014 8:27 AM in response to minimariobros64

    It was the GPU that was at fault. I fixed the problem by filing the two small cylinders on the heatsink down 1mm.

     

    Doing this has caused the heatsink to have a tighter fit against the GPU and the lines have now gone!