Dual Boot with OS X Lion and Mountain Lion – Step by Step Guide

Animal in New Mac OS X logo is not Really a Mountain Lion - It is Puma

I recently came to light the new operating system for Mac, OS X Mountain Lion , which includes important new features as we have been talking over these days. Since the news became known there are many who want to enjoy and the same and to investigate and test all you have to offer. Today we will show how to test the operating system without having to remove Mac OS X Lion of your computer and thus maintain a stable system.

Preparing to Install

First of all we must check the following:

OS X Mountain Lion , updating the Mac operating system that will be released this summer, will not be compatible with some Macs , especially those presenting chipsets and x3100 Intel GMA 950 . Additionally, it has published a list of computers that can not install Mountain Lion :

    1. Any team MacBook Intel Core 2 Duo 

late 2007 until late 2008 (Models: MB061 * / B, MB062 * / B, MB063 * / B, MB402 * / A MB403 * / A MB404 * / A, MB402 * / B)

  1. The Mac mini mid 2007 (Models: MB138 * / A, MB139 * / A)
  2. The polycarbonate iMac late 2006 (Model: MA710xx / A)
  3. The original MacBook Air early 2008 (Model: MB003LL / A)
  • Download the operating system from Apple (for developers), the Internet can find this download.
  • Make a backup. We recommend using Time Machine, but you can make a manual backup if you are more comfortable.

Installing OS X Mountain Lion

Once we have this you can get down to work. First of all, we need to prepare your computer for installation for this:

  • Open Disk Utility and in the left column select your hard drive.
  • Select the tab “Partition” and that will be displayed (if we have not done anything with the above) a single column corresponding to the partition of OS X we have installed.Clickamos on the “+” and appear before the same column divided in half.
  • We set the size and name of the partition (better name it with something like Mountain to avoid possible errors). For OS X Mountain Lion left over us with a partition of 15 gb.
  • Finally we give “Apply” and go.

Maybe some of you have problems (like I did) and do not let it create the partition, then what you should do is turn off the computer and turn hold Cmd + R, once loaded select “Utility Disk “and finally we give” Repair “. When the process and reboot and let us make the partition.

After that we only have to run the dmg we had previously downloaded a copy of OS X Mountain and when installation starts select as target the partition that we created.

Switching between the two systems

When you turn on your computer, we must hold down the Option key (Alt) to access the boot loader and there select the partition “Mountain” (or how you have named) and ready to wait for it to start first. You have in your Mac OS X device Mountain Lion.

If you get tired of having the new operating system you only have to do is delete the partition, but also eliminate cordaos Recovery as there may be problems if there are installed two at a time.


Posted by on February 22, 2012. Filed under Apple, Articles, Technology. You can follow any responses to this entry through the RSS 2.0. You can leave a response or trackback to this entry

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