What You Need
A UEFI compatible motherboard. Non-UEFI motherboards are not supported.
A 64-bit Intel processor. AMD CPUs are not supported.
A compatible graphics card. Intel Graphics HD 3000 and HD 4000 are supported, as well as most nvidia cards from G80 core to the newest kepler series. ATI/AMD cards are not supported.
A USB flash drive of at least 8 GB capacity.
A Mac or a Hackintosh to create the bootable USB drive. Windows is not supported.
The iATKOS ML3U.dmg file, which you can download from [here].
How to Create the Bootable USB Drive
Plug in your USB flash drive to your Mac or Hackintosh and open Disk Utility.
Select your USB drive from the left sidebar and click on the Erase tab.
Choose Mac OS Extended (Journaled) as the format and name it as ML3U (or anything you like).
Click on the Erase button and wait for the process to finish.
Click on the Restore tab and drag the iATKOS ML3U.dmg file to the Source field and your USB drive to the Destination field.
Click on the Restore button and wait for the process to finish. This may take some time depending on the speed of your USB drive.
Eject your USB drive and plug it into your PC that you want to install Mac OS X on.
How to Install Mac OS X Mountain Lion
Turn on your PC and enter the BIOS setup by pressing the appropriate key (usually F2, F10, F12 or Del).
Make sure that your BIOS is set to UEFI mode and that Secure Boot is disabled. Also, make sure that your SATA mode is set to AHCI and that your USB drive is listed as the first boot option.
Save and exit the BIOS setup and boot from your USB drive.
You should see the Clover bootloader screen with an option to boot from iATKOS ML3U. Select it and press Enter.
You should see the Apple logo with a spinning wheel. Wait for it to load the installer. If you get stuck at any point, try using some boot flags such as -v, -x, GraphicsEnabler=No, etc.
Once you reach the installer screen, choose your language and click on Continue.
Go to Utilities > Disk Utility and select the hard drive that you want to install Mac OS X on. Click on the Partition tab and choose 1 Partition as the layout. Choose Mac OS Extended (Journaled) as the format and name it as Macintosh HD (or anything you like).
Click on the Options button and choose GUID Partition Table as the partition scheme. Click on Apply and wait for the process to finish.
Close Disk Utility and go back to the installer screen. Click on Continue and agree to the terms and conditions.
Select Macintosh HD (or whatever you named it) as the destination for the installation and click on Customize.
Select the components that you need for your hardware configuration. You can use [this guide] as a reference. Make sure that you select the correct drivers for your graphics card, audio, network, etc. You can also select some optional components such as themes, wallpapers, etc.
Click on OK and then on Install. Wait for the installation to finish. This may take some time depending on the speed of your hard drive.
Once the installation is done, your PC will reboot automatically. Boot from your USB drive again and select Macintosh HD (or whatever you named it) from the Clover bootloader screen.
You should see the welcome screen where you can set up your Mac OS X preferences such as language, keyboard, network, Apple ID, etc.
Congratulations! You have successfully installed Mac OS X Mountain Lion on your UEFI PC with iATKOS ML3U.
Troubleshooting
If you encounter any problems during or after the installation, you can try some of the following solutions:
If you get a kernel panic or a black screen, try using some boot flags such as -v, -x, GraphicsEnabler=No, etc. You can also try to boot in safe mode by pressing F8 at the Clover bootloader screen and selecting Safe Mode.
If you have no sound, no network, or no graphics acceleration, make sure that you have selected the correct drivers for your hardware in the Customize section of the installer. You can also try to update or install some kexts (kernel extensions) using tools such as [Kext Wizard] or [MultiBeast].
If you have any other issues, you can search for solutions online or ask for help in forums such as [InsanelyMac] or [OSx86.net]. You can also check out [this guide] for more information and tips.
Conclusion
In this article, we have shown you how to create a bootable iATKOS ML3U USB drive and install Mac OS X Mountain Lion on a UEFI PC. This is a great way to enjoy the features and benefits of Mac OS X on your PC without having to deal with complex procedures or compatibility issues. However, keep in mind that this is not a legal or supported method and that you may encounter some problems or limitations. If you want to have a fully functional and stable Mac OS X experience on your PC, we recommend that you buy a real Mac from Apple.
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