Want to highlight a helpful answer? Upvote!

Did someone help you, or did an answer or User Tip resolve your issue? Upvote by selecting the upvote arrow. Your feedback helps others! Learn more about when to upvote >

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Level 1

0 points

iMac 27-inch, Late 2009 boots to grey screen

Hi,

I have had this Mac for almost 2 years but recently it has started to freeze up at random times. Upon reboot, it goes to a grey screen and nothing happens. I had to run Disk Utilities > Disk Verification > Disk Permission before I managed to boot it up normally.

From this forum, I tried installing smcFanControl and that worked for a while but the last time it froze while I was watching a DVD and that was that. Even running disk utilities was pointness. It just will not boot. The only way to run the machine was in safe mode.

Anyone has any ideas? I read about a lot of problems some people were habing with the ATI HD 4850 card. This machine happens to have one.

Chris

iMac, OS X Mountain Lion (10.8.2)

Posted on Dec 9, 2012 6:13 AM

Reply

4 replies

Level 1

74 points

Dec 9, 2012 8:12 AM in response to Xlim17

Were the temperatures high?

Did you try to install the OS again from scratch?

Do you have applications launching when starting the OS?

Reply

Dec 9, 2012 8:24 AM in response to Xlim17

See here about fixing grey screen at startup.

http://support.apple.com/kb/TS2570

Did you add any ram recently?

If yes, it could be incompatible ram.

Remove it and see if the iMac will start.

Any new peripherals?

Unplug anything that is connected to the iMac and see if it will start.

Reply

Level 1

0 points

Dec 10, 2012 3:37 PM in response to Stela

About 105 degress. I have yet to try reinstalling the OS. I have Mountain Lion 10.8.2 installed. Which OS do I install from scratch from, SL?

I actually turned off all applications but it didn't help.

Reply

Level 1

0 points

Dec 10, 2012 3:39 PM in response to Eric Fauque

Thanks. I will look it up.

Nope. No new ram. No new peripherals. I don't have a hard disk I use for time machine. I did unplug that but same old grey screen.

Reply

iMac 27-inch, Late 2009 boots to grey screen

Welcome to Apple Support Community

A forum where Apple customers help each other with their products. Get started with your Apple ID.

Learn more Sign up