Triple Boot -- Mac Pro 4,1 -- HELP!

[themacmeister]

Trying to get triple-boot working via GRUB2 on a real 2009 MacPro 4,1.

 

I had this working, and then re-installed Xubuntu 13.04 again, this time to MBR accidentally, ruining any chance of anything working correctly.

 

I wanted to have the TRIPLE BOOT Grub2 screen as a default, as it works with my non-EFI firmware graphics card, Apple's bootloader does not show at all with my GTX650.

 

I can currently boot Windows7-64bit and Xubuntu 13.04 64bit from Grub2.

 

Trying to launch OSX goes through all the lead-up, but then I get "Still waiting for root device"

 

Booting either BOOTCAMP partition, or Linux partition (which only shows as Disk3) results in the Grub2 menu.

 

This tells me me I did replace the MBR when I installed Linux.

 

If anyone has recovered from such a situation, and been able to reinstall Grub2 to Linux partition, and then recover the Win7 MBR, that information would be most appreciated. I would not mind reinstalling Linux, but Win7 and Mountain Lion OSX installs are too advanced to start again. Here is my current partition layout (for OS'es):

 

Partition 1 (SSD on ASM1061 SATA3 card) Mac OS GPT boot partition + BOOTCAMP windows boot partition->equal 128GB each, Linux on a separate 1TB HDD.

 

Any and all help gratefully accepted 

EDIT: I can boot back into OSX from the Windows BootCamp control panel, and I can also set OSX as a default from here, or Mac OS X Startup Disk control panel too.

 

EDIT: It appears as though I can use gdisk to create a hybrid-MBR with OSX then Win7, and write changes. This *should* fix the "grub always loads first" problem I have been having?! I will give this a try tonight (after doing a full time machine backup).

[redneck]

THis is why I have Maverick installed on a usb drive.> boots up on my HP7700

I would try to install latest Chameleon boot loader. > ML or try usb.

I boot to other OS from  Chameleon at boot > f8

You can update to Maverick free.

[themacmeister]

I have the problem of having no boot screen, due to a non-efi firmware graphics card. As an example, rEFIt does not show its boot screen on startup

 

Grub2 DOES show it's text only screen... but the Mac OS X entry is corrupt/wrong.

 

I would love a triple-boot system without any hassle, and it looks like Grub2 can do this (albeit with verbose booting for OSX).

 

There is also the possibility of using EasyBCD, which can boot all three OSes, but I have had NO SUCCESS using this tool in the past. Also, EasyBCD will probably not show a boot screen at startup, due to graphics hardware non-EFI as stated above...

 

It really looks as tho I need to reinstall Xubuntu, and make sure I place the boot files on the linux / PARTITION, *NOT* the MBR (which is how I got into this mess). If I still have my var/cache/apt/archive still backup up, I will certainly give this another chance. It may also fix the OS X ML boot issue I have been having.

 

EDIT: I am using Tuxera NTFS, which seriously screws with Boot Camp (windows) booting. I am using Boot CHAMP software to quickly switch to Windows, but at the moment, it is loading Grub2 instead.

 

EDIT: I do not want to update to Mavericks just yet. I had enough problems with software compatibility switching from Lion to Mountain Lion.

 

EDIT: It looks like I can reinstate the correct MBR in Windows 7 using the install DVD (and Repair your Computer selection). I will investigate this further.