Installing XP onto a Vista/Ubuntu (Grub) PC?

[th0r0n]

Hi guys,

I have a PC running Vista64 OEM at the moment on a 400GB partition, and then used G-Parted to auto-install Ubuntu Linux with the GRUB Bootloader on the remaining 100GB.

I want to install XP as overclocking tools seem more reliable in XP (Whether I go back to Vista is debatable, it's a good OS but I want DirectSound and my overclocking tools to work, plus if games run a bit faster that'd be nice)

Can I just use G-Parted to put aside say another 100GB of space for XP and install? I presume I will overwrite my MBR, thus making my Linux and Vista O/S inaccessible?

Can I run GRUB from a boot disk/USB Key to add the new OS?

Thanks, and sorry for the newb question, my spec is correct if you need to click that

T

[MSIC]

Someone else will give you a more technical side of things, but i can tell that under normal (ie following onscreen instructions) conditions, installing any Windows AFTER Ubuntu will overwrite the MBR, GRUB won't load and that's that.
As a rule of thumb, Linux should be the last thing to install.

So given your situation, i'd be tempted to save off your personal data and start again, but i'm sure there is some technical way around it

[peterb]

There is a way round this, which involves writing the MBR to a floppy, and then installing teh new OS.

Basically...

Create the new partition fort he new OS.

Copy the MBR to a floppy

Install new OS - making sure you install it to the correct partition - and make a note of where it is.

Re-install the MBR from the floppy (easiest way is to boot from a live linux CD)

Modify the grub.conf file to set up the menu and chain loader to give the option to boot the new OS.

You could do a complete re-instal of grub itself, which I think would take care of all that for you.

Whichever route you go - back up all your critical data first!

This link will start you off

GNU GRUB Manual 0.97

[8bit]

Unlike most Linux distributions, Windows installer will just overwrite the MBR with it's own bootloader code regardless of whatever's there already so as has been pointed out it will wipe out access to your GRUB bootloader.

I don't have access to an Ubuntu machine here at work but I'm pretty sure if you fire up your Synaptic Package manager and search for "grub rescue" there's a tool (probably with a nice GUI) you can use to create a rescue floppy for your system. If you're comfortable with shell commands I think "grub-install" can be used if you boot from the Ubuntu LiveCD after some version of Windows has trashed your GRUB boot code. Do a "man grub-install" from a terminal window running off the live CD.

[directhex]

what people are neglecting to mention is the REAL issue - installing xp after vista. xp after linux isn't an enormous problem if you reinstall grub (as described by peterb)

grub doesn't directly boot xp or vista, it "chain loads" the xp or vista boot loader. multiple windowses are handled by the windows boot loader, not grub. but if you install xp after vista, then even after restoring grub, you have an issue with vista's boot loader having been overwritten by xp's

sounds like you've done things in the worst possible order, really