Triple booting now; will 'upgrade' disable XP?

I'm planning on taking advantage of the price cuts announced today and would like to run W7 home Premium. I am currently triple booting with partitions for XP, W7-RC, and Linux. Would installing an upgrade version of W7 overwrite or otherwise disable the XP system, or would I need to purchase a 'full' version? I want to be able to keep that as is for the other member of the household.

Thanks!

Unless you had a spare partition or spare drive to install on (And tell it to use that one during the install set up), it would overwrite the current OS you are using when you put in the CD.

The problem is if you install it it will create a new boot manager and I'm going to guess you'll at minimum loose the ability to boot into linux... I'm not entirely sure how it will handle a 3-4 OS boot setup.

It wont delete your XP partition if you dont install it on their, their wont be any conflicts part from the boot manager change Kougar mentioned. Apart from that no, Windows 7 wont disable XP. It is the same way you installed the RC version.

So the Upgrade CD is intended to be run from within an existing OS? What I want to do is simply replace the W7-RC1 installation with W7 Home Premium without affecting either XP or Linux. On a 500GB drive, I have XP on primary partition #1, W7 on #2, and a 300GB data partition on #3. Linux Mint is on a logical partition.

EasyBCD should handle reconfiguring the bootloader with a minimum of fuss.