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

iMac display screwed up, and It's not the ATI Graphics card or Logic Board

Hello,

I'd like to thank you in advance for the support.

I believe this is a software issue, but I CANNOT fix it! Please help!

I have a ATI Radeon HD 4670 (or wahtever version) and I have 15 1/2 inch pixilated spots all around my screen. I have tried a different moniter..no success. I saw a support forum which demanded I delete the drivers, still...No luck!! I cannot access my mac unless I'm in safe mode, or recovery HD. The safe mode actually works. If this were to be a graphics card problem or Logic board problem, It would not work...

The cursor in Recovery HD mode has lines around the bottom left... Please help me, and I'll thank you..I depend on this mac for my job! It's a iMac 2010 21.5" 500 GB! I've changed the HARDDRIVE aswell!



Thank you all!

iMac, Mid 2010

Posted on Feb 5, 2014 3:14 PM

Reply
6 replies

Feb 5, 2014 3:43 PM in response to Noah_Lauzier

I take it that's when you check the Scaled button in Displays preferences? That's the native display size. But I would think other resolutions should be present. It's an artifact of an installation screwup, I believe.


Here's how to perform a fresh installation of whatever version of OS X installed the Recovery HD.


Install or Reinstall Mavericks or Mountain Lion from Scratch


Be sure you backup your files to an external drive or second internal drive because the following procedure will remove everything from the hard drive.


OS X Mavericks- Erase and reinstall OS X

OS X Mountain Lion- Erase and reinstall OS X

OS X Lion- Erase and reinstall Mac OS X


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

because it is three times faster than wireless.


The above does not repartition the hard drive. It just erases it. To repartition AND reformat the hard drive you will need to boot from the installer DVD that came with your computer UNLESS your computer came with Lion pre-installed. In this case you can use Internet Recovery to essentially start from scratch. But your computer must be able to use Internet Recovery: Computers that can be upgraded to use OS X Internet Recovery. If this be the case:


Install Mavericks, Lion/Mountain Lion Using Internet Recovery


Be sure you backup your files to an external drive or second internal drive because the following procedure will remove everything from the hard drive.


Boot to the Internet Recovery HD:


Restart the computer and after the chime press and hold down the COMMAND-OPTION- R keys until a globe appears on the screen. Wait patiently - 15-20 minutes - until the Recovery main menu appears.


Partition and Format the hard drive:


1. Select Disk Utility from the main menu and click on the Continue button.


2. After DU loads select your newly installed hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.


3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed. Quit DU and return to the main menu.


Reinstall Lion/Mountain Lion. Mavericks: Select Reinstall Lion/Mountain Lion, Mavericks and click on the Install button. Be sure to select the correct drive to use if you have more than one.


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

if possible because it is three times faster than wireless.


This procedure will install the pre-installed version of OS X (likely will be Lion.)

iMac display screwed up, and It's not the ATI Graphics card or Logic Board

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