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screen goes black after installing Mountain Lion or Yosemite

After upgrading to Mountain Lion from Snow Leopard, my iMac screen goes to black and must do a hard restart to clear. Has anyone had this issue and if yes, what's the solution, will more memory help? My 24" iMac has 2GB.

iMac, Mac OS X (10.5.8)

Posted on Mar 28, 2015 11:38 AM

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11 replies

Mar 28, 2015 11:42 AM in response to cherish2013

Add more RAM to your computer. 2 GBs is simply not enough, but that isn't the cause of the problem.


Reinstalling OS X Without Erasing the Drive


Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.


Reinstalling OS X Without Erasing the Drive


Repair the Hard Drive and Permissions: Upon startup select Disk Utility from the main menu. Repair the Hard Drive and Permissions as follows.


When the recovery menu appears select Disk Utility and press the Continue button. After Disk Utility loads select the Macintosh HD entry from the the left side list. Click on the First Aid tab, then click on the Repair Disk button. If Disk Utility reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit Disk Utility and return to the main menu.


Reinstall OS X: Select Reinstall OS X and click on the Continue button.


Note: You will need an active Internet connection. I suggest using Ethernet if possible because it is three times faster than wireless.


Alternatively, see:


Reinstall OS X Without Erasing the Drive


Choose the version you have installed now:



OS X Mountain Lion- Reinstall OS X



Note: You will need an active Internet connection. I suggest using Ethernet

if possible because it is three times faster than wireless.

Mar 28, 2015 12:41 PM in response to cherish2013

To find the model identifier open System Profiler in the Utilities folder. It's displayed in the panel on the right. Please post it. or see,


Upgrading to Yosemite


You can upgrade to Yosemite from Lion or directly from Snow Leopard. Yosemite can be downloaded from the Mac App Store for FREE.


Upgrading to Yosemite


To upgrade to Yosemite you must have Snow Leopard 10.6.8 or Lion installed. Download Yosemite from the App Store. Sign in using your Apple ID. Yosemite is free. The file is quite large, over 5 GBs, so allow some time to download. It would be preferable to use Ethernet because it is nearly four times faster than wireless.


OS X Mavericks/Yosemite- System Requirements


Macs that can be upgraded to OS X Yosemite


1. iMac (Mid 2007 or newer) - Model Identifier 7,1 or later

2. MacBook (Late 2008 Aluminum, or Early 2009 or newer) - Model Identifier 5,1 or later

3. MacBook Pro (Mid/Late 2007 or newer) - Model Identifier 3,1 or later

4. MacBook Air (Late 2008 or newer) - Model Identifier 2,1 or later

5. Mac mini (Early 2009 or newer) - Model Identifier 3,1 or later

6. Mac Pro (Early 2008 or newer) - Model Identifier 3,1 or later

7. Xserve (Early 2009) - Model Identifier 3,1 or later


To find the model identifier open System Profiler in the Utilities folder. It's displayed in the panel on the right.


Are my applications compatible?


See App Compatibility Table - RoaringApps.

Mar 28, 2015 1:49 PM in response to Kappy

Before the original post, I tried both Lion and Yosemite, both worked fine for a while but then the screen goes black... There is nothing on the screen, so I must keep doing hard shutdowns...and the cycle begins again - works fine, black screen, hard shutdown - works fine, black screen, hard shutdown!!! Not very productive... Is there a fix for the screen going to black?

Mar 29, 2015 8:32 AM in response to cherish2013

Try adding RAM. The 2 places I’ve seen recommended most to buy reliable RAM are below. I have purchased RAM several times from Other World Computing and have always been very satisfied with the product and service. They have on-line instructions on how to replace the RAM. OWC has also tested RAM above what Apple states is the maximum. I now have 6GB installed on a early 2008 iMac supposedly limited to 4 GB and noticed an improvement.


Crucial


Other World Computing

screen goes black after installing Mountain Lion or Yosemite

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