Imac 27 (2010) shows white screen

[jacobDK]

My IMac 27" shows five vertical stripes on a white background when I turn it on, while also showing the progress bar for starting up.
After that the screen turns completely white and only shows the mouse arrow with thin horisontal lines around it. It stays that way.
The IMac uses the latest IOS.
Any good ideas? Thanks a lot, Jacob

 

[redheeler]

Sounds like a failing GPU.

Edit: Try booting to Recovery (hold down Command-R at boot) to see if something similar happens.

 

[jacobDK]

Tried Command-R at boot. Get a list of options (re-install OS X, recover from time-machine etc). So the computer reacts to input.
I can select theses options and open a browser to go to apple help page, open disk aid and so on. The vertical stripes are still there.

When I reboot the stripes are stille there while mac boots and then the screen goes to pitch black - which is new - and stays there. I can hear the harddrive working as normal.

Sounds like I should get a new GPU?

Thanx a lot for your help, redheeler!

 

[redheeler]

If you can boot into Recovery without issue do an OS reinstall from there.

 

[jacobDK]

Did an OS reinstall. The vertical stripes showed all the way through the proces. When mac restarted it still showed the vertical stripes at boot and then the white screen as before ...

 

[redheeler]

Then it's likely a failing GPU as I had guessed. While the GPU is replaceable in that model it's not an easy or cheap repair and probably not worth it for your 4+ year old machine.

 

[jacobDK]

I will ask my local service centers for a replacement price.

Thanks a lot for your advice redheeler - it has been a great help for me!

 

[willmtaylor]

I will ask my local service centers for a replacement price.

Thanks a lot for your advice redheeler - it has been a great help for me!

I know it's been a long time, but I've just started having an identical issues with my 27" 2009 iMac 11,1.

What did you end up doing?