Here's a HowTo on how to install OSX, WinXP, Vista, and Linux(s) with swap, universal storage partitions and any other partitions you require, and Grub hiding in between the WinOS to keep them isolated from each other -- on one hard drive.

It all stared when I got a MacBook Pro for uni, and I wanted a multi-OS setup like my desktop, documented here: HowTo: Multiple, Independent WinXP Installs on the Same HardDrive via Grub. Only I wanted to substitute Vista in of a secondary WinXP install, and OSX naturally being added to the list.

After a ton of googling and picking away at EFI/MBR hybrids and refit et al. I finally stumbled upon the secret on this ubuntu forum thread - OSX will not install to a MBRed hard drive, but will function if you push an image to a MBRed hard drive.

My final setup:
1- OSX
2- WinXP
3- WinVista (once MSDN kicks in)
5- Linux Swap
6- Universal Data Directory (Fat32)
7- Linux Distro
8- Linux Distro
~20GB free for more distros as desired or perhaps for a temp storage need.

Have to hold option to bring up options, otherwise it boots straight to OSX. With options held you get two options: OSX and WinXP. Upon selection of WinXP, Grub is loaded. So you can do Grub hiding between WinXP and Vista which is exactly what I want, and of course you can choose from whatever distro you feel like booting.

Learned a good bit about EFI and could have potentially gone that route now that apparently Vista will support EFI after SP1, but I'm absolutely loving this simple and easy (definitly easy compared to hybrid EFI/MBR routes) MBR route, except for the slower OSX boot time. That default GPT OSX config boot time can be addicting lol.


Anyway, thought this might be of interest to some. My only real complaint is I can't do OSX, WinXP, Vista, Linux + BSD as every BSD I know of are primary partition kosher only...but you can only ask for so much.

DrCR

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A5N8X, 3500+ single-core Manchester, 2x512MB Corsair XMS, MSI 7600GT
S-12 430W, HR-05, Scythe Mime, VF900 modded with Scythe 80x25mm. Dual D12SL-12 Yate Loons
WD1200JB, WD3200JB, HD501LJ
Dual,independant WinXP installs via Grub hiding, VectorLinux 5.1.1SOHO, 5.8SOHO.
- - - - -
MacBook Pro Santa Rosa, 2.2GHz, 250GB Scorpio, Ceramique compound, Pending Appled-Tux Logo mod
MBRed Hard Drive with: OSX, WinXP, Vista (MSDN), Vector 5.8 SOHO, Sidux 2007-03
Pending Fusion "bootcamp" VMs pointing to native OS installs