Triple Boot - Mac OS X (Lion 10.7.2), Windows 7 x32, & Windows 7 x64

Discussion in 'Windows, Linux & Others on the Mac' started by JV224, Jan 17, 2012.

  1. JV224 macrumors newbie

    Jan 17, 2012
    This past December, I ordered a 13" Macbook Pro and also bought a copy of Windows 7. I'd like to have the 32bit version of Windows installed as I have older software that doesn't run on the 64 bit version but want the 64 bit version to run newer applications as I only get ~2GB of available RAM in the x32 version. I've tried installing one version within bootcamp and then adding another partition (MSDOS format) manually in disk utility and installing the other version on that partition. However after the latter installation, I can only boot into the version of windows that was last installed, although I could boot back into Lion. It doesn't seem to make a difference which version of windows is installed first. Does anybody know how to get this triple boot to work?
  2. johnhurley macrumors 6502a


    Aug 29, 2011
    As far as I know I think most of the people running triple boot setups are using rEFIt?

    Most win 32 apps run ok under win 7 64 and there is special settings/tweaking that one can do ( might be available just under win 7 pro ... not quite sure about that ) for compatibility options.
  3. JV224 thread starter macrumors newbie

    Jan 17, 2012
    Solution for Triple Booting Lion (10.7.2), Win7 x32, and Win7 x64

    In short, this involved backing up the Lion recovery partition to a usb flash drive, deleting the recovery partition from the hard drive, adding two MSDOS FAT partitions, then installing both versions of Windows 7 (32 and 64 bit). Please read this post in its entirety as well as the two links I referenced before trying anything. Below are the details and the reference sites: and

    First of all, thanks John for the reply. I don't know that rEFIt is compatible with Lion (10.7.2) or that it will support triple booting with Lion, Windows 7 32bit, and Windows 7 64bit. I did buy the Pro version of Win7 and with that one can download a Windows XP compatibility mode virtualization program from Microsoft. However, I not too interested in running windows virtualization within Win7 as I'm not sure how it will handle games and graphics. Also, I couldn't get a usb joystick and printer to work within Microsoft's Virtual PC.

    Regarding compatibility, various older programs (from late 90s to ~2007) didn't work in Win7 x64 even if I were to run in compatibility mode for say Win XP or Win 98 etc. Some of these programs did work fine however in Win7 x32 without running them in any compatibility mode.

    Now finally here is the procedure I used to triple boot Lion, Win7 x32, & Win7 x64. First, of course, make sure you have a backup of all relevant files and that you have reinstallation discs or downloaded setup files for any programs you that aren't included in Lion in case something goes wrong. Also you'll need a bootcamp drivers CD so create one within bootcamp if you don't already have one.

    Go to and download the Lion Recovery Disk Assistant. Since you'll be deleting the recovery partition from your hard drive, it's strongly recommended that you back it up to a flash drive. Install and run the program. Insert a blank usb flash drive that isn't going to be used for anything else (I used a 1gb size flash drive--not sure how much smaller a size is allowed) and use the program to create the backup of the recovery partition. It will reformat the flash drive when doing so. After this is done, check to see if this backup recovery drive works properly. With the flash drive still in the usb slot, restart the computer while holding the option key and boot from it. If everything's ok, this should be identical to booting from the recovery partition on you hard drive. Now reboot back into Lion.

    The next steps are referenced from but I'll restate here. Go to Utilities and open Disk Utilities. Click on your hard drive (NOT one of the partitions below it) and click on the Partition button. Resize the Macintosh HD so that it's ~1GB smaller than the full disk and click apply.

    Microsoft Windows 7 seemingly only allows there to be 4 partitions max, otherwise it won't proceed with installation. Go to Utilities (within Lion of course) and open Terminal. Type without quotes "diskutil list" and hit return. The output should be

    • disk0s1 EFI (Boot) ~200MB
    • disk0s2 Mac OS X 10.7
    • disk0s4 Mac OS X Recovery

    Thus we're going to delete the recovery partition and create two new MSDOS FAT partitions, one for each version of Win 7. To delete "disk0s4 Mac OS X Recovery" within Terminal, type in without quotes "diskutil eraseVolume HFS+ Blank /dev/disk0s4". Now go back into Disk Utility and delete the "blank" partition and click apply. Stretch Macintosh HD to the full available space using Disk Utility and click apply. Check your partition list using "diskutil list" within Terminal and the output should be

    • disk0s1 EFI (Boot) ~200MB
    • disk0s2 Mac OS X 10.7

    Within Disk Utility, add two new partitions and size them to whatever you want them to be bearing in mind the minimum space required for Win7. Of course, one partition will be for the 32bit version and the other for the 64bit version, so size accordingly. You can name one bootcamp32 and the other bootcamp64 or win32--whatever you wish. Before clicking apply, make sure the format of the two added partitions is MS-DOS (Fat). Click apply, and after the new partitions are created, insert your Windows 7 installation disc for either the 32 or 64 bit version, whichever you wish to install first.

    Restart your computer holding the down the option key and boot from the Windows 7 disc. Choose the advanced installation option, not the upgrade option. When asked where to install Windows, select one of the Fat partitions you just created that you'd like to install whichever version of Windows you're installing first, click drive options (advanced), format it to NTFS and proceed with the installation. When the computer reboots, if it reboots back into Lion, reboot while holding the option key, and select the Windows option, not the Windows CD. After the Windows installation has finished, install the Windows support software from the bootcamp drivers CD. Afterward, verify that you can boot back into Lion.

    Before proceeding with the 2nd installation of Windows, I recommend having Windows being the default operating system so that when the computer reboots during installation, it doesn't boot back into Lion. Just change this within the bootcamp control panel within Windows. Insert the other Windows 7 installation disc and reboot holding down the option key and boot from the CD. You may have to hit return quickly as you may be asked if you want to boot from the disc. Proceed as before but selecting the other Fat partition you created earlier, format it as NTFS, and install the other version of Windows 7 (32 or 64bit). When rebooting into windows you'll see table with two options, both of which state Windows 7. If I recall correctly, select the first one and hit return. If this is indeed the version of Windows you're finishing up installing, proceed with installing the Windows support software and bootcamp drivers. If it isn't, reboot and select the 2nd listed Windows 7 from the table.

    Hopefully at this point, both the 32 bit and 64 bit versions of Windows 7 have been successfully installed and that you're able to reboot into Lion as you desire. To change the menu names of the two Windows versions that appear and to set a default one after a specific time interval provided you're booting into Windows rather than Lion, I used a program called Easy BCD.
    (This should be free for non commercial use.)

    With that, I changed the names of both the Windows 7 operating systems from "Windows 7" to "Windows 7 32 bit" and to "Windows 7 64 bit" and set a timer to default to the 32bit version after 10 seconds or so.

    Hopefully this works out for you as it did for me.
  4. vistadude macrumors 65816

    Jan 3, 2010
    Instead of triple booting, you could install windows xp mode under windows 7 64 bit for old programs/installers. Also, 32 bit programs run under 32 bit mode in windows 7. Even Internet explorer and office run under 32 bit mode by default.


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