
I've looked all over the web for information on installing Snow Leopard on the MSI X58 Platinum motherboard, only to find spotty support and advice. Most of the guides I found required downloading an older distro of Leopard 10.5.x, installing that first, then installing Snow Leopard. By following some parts of these guides and peicing together the rest on my own, I present a more straightforward guide, that is a direct retail install requiring no access to another Mac or Hackintosh, and no distro to download.
A NOTE: I wouldn't recommend purchasing this board specifically for OSX. It runs OSX well, but there are far better (and newer) boards to choose from. This guide is for those who already have the MSI X58 Platinum and are interested in running OSX on it.
Here's what you'll need:
1. Retail OSX Snow Leopard DVD (as of this writing, 10.6 or 10.6.3)
2. Download iBoot and Multibeast from Tonymacx86. (Optional: You can also download the OSX 10.6.5 update Combo from Apple's website). Only use the Combo update, the non-combo update will not work.
3. A blank or unused SATA hard drive to install OSX, installed in your computer, and an OSX compatible graphics card, IE: nVidia 9xxx series, or GTX2xx series.
4. About 45-60 minutes and an ability to follow instructions and figure common computer tasks out.
Okay, let's get to it. Before you start, download iBoot from the above link and burn the .iso file as a disk image to a blank CD. If you don't know how to burn an .iso image, use Google to look it up (see the last part of item number 4 above). Also, copy Multibeast to a CD or USB flash drive- whatever makes it easiest to transfer to your soon-to-be-Hackintosh. Ditto: the OSX 10.6.5 Combo Update (about 1GB) from Apple, if you've pre-downloaded it at this stage. Otherwise, you can download it later after the initial install.
BIOS PREP:
1. We're going to set up the BIOS of the MSI X58 Platinum. Hit delete at bootup, and enter SETUP. Once in, arrow down to Integrated Peripherals. Enter- arrow down to On-Chip ATA Devices. Set RAID mode to AHCI. (Note: If you already have Windows installed on your machine and you haven't set this, you will need to edit your registry to allow Windows to boot without an instant BSOD.)
2. Escape back out to the BIOS main page and enter Power Management Setup. Enable ACPI Function, and make sure ACPI Standby is set to S3. Escape back out, and go to Advanced BIOS Features. Arrow to Boot Sequence, and enter. 1st Boot should be your DVD drive, 2nd Boot the hard drive you'll install OSX onto. You should be good to go. Escape back out, and Save and Exit Setup.
BOOTING iBOOT:
3. Put your burned iBoot disk in the drive and boot the computer. When you see the below screen, eject the iBoot CD.

[Click images to view full size.]
4. Insert the Snow Leopard DVD and wait for it to spin up. Hit f5 to refresh the boot screen. The SL disk should be selected. DO NOT hit return just yet or you will get a Kernel Panic. Type: -v cpus=1 busratio=20. (You will see this text at the bottom of the screen).

Now hit enter. You'll see a black screen full of white text scroll by. Wait for SL to boot to a graphic start screen. Choose language and continue.
SETUP YOUR HARD DRIVE:
5. When you get to the Install Mac OSX screen, go to the Utilities menu at the top. Open Disk Utility. Choose your OSX disk, and click Partition. From Volume Scheme, choose at least two partitions- one for your main install of OSX, another of roughly 20 GB for your backup install. (This is a method other guides never stress- ALWAYS have at least one backup install of OSX and you're covered. Multiple copies of OSX can be run from the same drive, or multiple hard drives.)

IMPORTANT: Before you click Apply, click the Options tab and make sure you select GUID. Apply your partition settings and exit Disk Utility.
INSTALL OSX SNOW LEOPARD:
6. Hit continue, agree, and select your main install partition. (Later, you'll repeat this process and select the backup partition). Click Customize. Choose the options you want. For the backup partition, you'll probably want have all deselected for the leanest possible install. Click OK, and Install. It will take about 20-30 minutes for OSX to install to your drive.
POST INSTALL SETUP AND UPGRADE:
7. After Snow Leopard installs, reboot. (At shutdown, you'll see more white text on black, since we booted using the -v flag). Eject the Snow Leopard DVD from the drive and replace with iBoot CD again. This time when you get the boot screen, you should see your OSX partitions. Select the one you just installed OSX to, and return. [You should now be able to boot directly, but if you have a KP, redo this step and use: -v cpus=1 busratio=20.]
8. You should see the OSX welcome animation. Setup your OSX with location, user name, password, keyboard, etc. (You can continue past Apple ID and Command+Q {Skip} out of Registration Information.)
9. Copy all your needed tools over to the OSX desktop. (Specifically, MultiBeast, and if you downloaded it earlier, the 10.6.5 Combo Update.) If you didn't download the 10.6.5 Combo update earlier, you can connect to Ethernet now and download it from Apple. (Ethernet should work Out Of the Box). Run Software Update 10.6.5.

When done, it will say it needs to restart, but don't restart yet. Just leave the OSX installer open.
INSTALL MULTIBEAST:
10. Open the Multibeast installer file. Select the following options from the checklist:
- EasyBeast
- Kexts/Audio/VoodooHDA 0.2.61
- smbios.plist/Mac Pro Core i7 (or you could also select iMac i7)
- OSx86 Software

11. Click continue, install, and restart. Important: remove the iBoot CD from the drive before rebooting. The system should now boot on its own.
12. You should be greeted by a brand new install of OSX 10.6.5 running on your MSI X58 Platinum!


Note, I installed the above system as an i7 iMac under smbios.
BACKUP!
13. Remember our backup partition created in step 5? Where here is where we make use of it. Basically, the most straightforward method is just to repeat all the steps above starting back again at step 3- insert your iBoot CD. You'll skip step 5 of course because our drive is already partitioned. Do the same installation again, only select MAC2 as your target. Keep in mind, even though you've already installed the Chameleon bootloader on your hard drive, you should continue to use the iBoot CD to boot your MAC2 partition through the install until you complete step 7, the 10.6.5 Update and Multibeast installer. (Note: locate the same Combo 10.6.5 installer download on your MAC1 partition rather than waste time downloading it again.
14. Of course, if you're more tech-savy, you can merely clone your MAC1 OSX install to MAC2. Either way, the goal is to have not one but two working installations of OSX on the same drive. Leave the MAC2 installation in pristine condition. If anything ever happens to your MAC1 install that keeps it from booting (say, an OS update that creates a problem) then you can always boot from MAC2 and get back into your system. From MAC2, you can even do basic repair tasks on MAC1 to restore it to boot status. Think of it as a 2GB insurance policy, and always a mandatory safety precaution when using a Hackintosh.
GRAPHIC CARD NOTE: If your graphics aren't fully enabled, you might have to install graphic drivers, IE: use an EFI string or other tool for nVidia graphics cards. For many supported nVidia graphics cards, the string "GraphicsEnabler=yes" in the com.apple.Boot.plist file (in EXTRAS folder) is usually enough. You'll know your graphics card isn't fully enabled if you can't change screen resolutions and/or the menu bar at the top of the screen isn't slightly transparent. To be sure Core Image and Quartz Extreme are enabled, open up dashboard (tap F12) and drop any dashboard widget onto the desktop. If you see a ripple effect, you're good to go. If not, you don't have hardware rendering enabled.
I recommend stick with nVidia cards for best results. Certain models of ATI cards can be made to work, but from my experience it requires a lot more hoop-jumping. Hit the insanelymac.com support forums for further information on graphic card support.
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NOTES ON WINDOWS DUAL BOOT:
If you install Windows 7 (or God forbid, Vista) AFTER you've installed OSX, follow these basic guidelines:
1. Keep Windows and OSX installs on separate hard drives to preserve your sanity. Yes, OSX and Windows can be installed on the same drive, but the process is a PITA, and not the ideal dual-boot desktop.
2. Make sure AHCI is enabled in the BIOS at the time of install. (See BIOS PREP step 1). If for some insane reason you want to install Windows XP, then you'll have to turn AHCI off.
3. Very Important- DISCONNECT the OSX drive and all other non-Windows drives from the system before you begin installing Windows. You can either pull the SATA cables or power cables to the drive(s). Windows will very likely screw up your OSX bootloader if you leave it installed in the system, and definitely if the OSX disk is your primary boot drive.
If you've already installed Windows Vista or 7 prior to installing OSX, but you didn't have AHCI enabled in the BIOS at the time you installed Windows. In this case, Windows WILL fail to boot with a very quick BSOD and restart. Luckily, there's a very simple fix:
1. Enter the BIOS and go to On-Chip ATA Devices. Change AHCI mode back to IDE mode.
2. Boot into Windows, click start, type Regedit.
3. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE / System / CurrentControlSet / Services / Msahci
4. In the right pane, right-click Start in the Name column, and then click Modify.
5. In the Value data box, type 0, and then click OK.
6. On the File menu, click Exit to close Registry Editor.
7. Restart the computer, enter the BIOS, go to On-Chip ATA Devices and once more enable AHCI. Boot Windows (If your OSX drive is the default boot drive, you can choose it from the Chameleon bootloader). Windows should start without a BSOD, and then begin installing the AHCI drivers. (Be patient and let it finish this process.)
Another restart after the driver install, and your system is now fully dual-bootable with AHCI enabled for both OSX (necessary) and Windows.
EDIT: Here are links to the exact versions of MultiBeast and iBoot I used for the above tutorial. Newer versions may not continue to work with the MSI board. These are rapidshare links- if they expire, leave a comment and I'll repost the files.
MultiBeast
iBoot