Will installing Windows on a separate disk mess up my existing MBR?

Question

I have a spare HDD sitting around I'd like to put Win XP on; it's currently formatted/mounted as an extra NTFS volume on my Ubuntu 9.10 install.

If I install XP on the drive, will it wipe-out/modify my existing MBR? I haven't dealt with Windows in so long, I can't remember how it behaves when dual-booting from a separate disk.

Here's the setup I have:

• Primary Drive: 3-partition, ext4: /home, /, swap
• Secondary Drive: 1-partition, NTFS

My concern is wiping out the MBR which allows me to boot into my Linux system. Since it's being installed on a separate volume, I would expect my Linux data to be safe; I'm just not sure if it will screw up the MBR, causing me more headaches when trying to boot into Linux.

Answer 1

The best thing to do would be disconnect your primary drive during the installation. WinXP's installer will write itself to the MBR, but after the installation is complete, your BIOS should boot to your reconnected primary drive and you'll get the Grub menu.

Add this to Grub v1's menu.lst file to add a menu entry for the new installation (assuming WinXP installed on the secondary drive's first partition):

title          Windows XP Pro
root           (hd1,0)
makeactive
chainloader    +1

Note you may need to update Grub's devices.map file to specify what device (hd1,0) is.

Answer 2

Unfortunately, I am not sure if installing Windows this way will mess up your MBR (I'm more of a Linux user myself ;))

However, you should be able to recover the MBR in case this happens by following the guide available at https://help.ubuntu.com/community/RecoveringUbuntuAfterInstallingWindows

Hope this helps.

Answer 3

You should have no problem installing XP to a slave drive, as long as the BIOS is set to boot from the first hard disk. The MBR should be written to the disk you specify when installing.