Desire to keep WinXP on Mirror RAID with Win7 on separate HDD

Simplest thing to do is to just load W7 and get it over with...but am just smart or stupid enough to consider alternatives...

I have a pretty stable WinXP install but have run into games that require 7 (and DirectX 10).

Question:

Can I install W7 on a non-raid HDD (already on my machine) while keeping WinXP on the 250 GB mirror thus avoiding application reload AND potential for issues with the RAID array?

My initial thought is to unplug the mirrored drives and install W7 to the single drive. Replug the mirrored HDDs (same ports). Edit the Boot sequence to allow choice of XP or 7.

How badly would this go?

Not well with Win7, which doesn't much like RAID.

A lot depends on the controllers which will need to provide both RAID for XP and SATA/AHCI for Win7.

You can try booting WIn7 to see if it sees the target HD, then try install.

If this fails, unplug the RAID while taking careful note of its settings, try install of Win7 to target HD with nothing else plugged in at all. The SATA controller should be in AHCI mode.

I've been doing some prep work b4 trying this out.

One issue: Assume I can load W7 on the standalone HDD (maybe having to be done with RAID HDDs disconnected or not). How does the system know - when I plug the RAID drives in to offer a boot choice of W7 or WXP?

I found BCDEdit which apparently allows you to edit the boot loader for Win7. However, boot.ini (for WinXP) in the root of my C:\ drive cannot be used to reference or otherwise initiate the start up of W7 (so I've read).

I haven't checked yet but would this then "simply" require a bios change in the order in which it looked for OS? Point it at Drive 1 (Win7 location), then the RAID (Drive 0). I haven't looked at BCDEdit enough yet to know if it would offer the choice I want but it seems that it would.

Any thoughts or comments welcome. Thanks.

Follow up:

I checked my BIOS out. I think I would have a SATA/AHCI issue as my Ob Chip SATA Type choices are:
-Native IDE
-RAID - [this is the setting]
-AHCI

On Chip SATA Port 4/5 Type (the 5th and 6th SATA ports) choices are:
-IDE
-As SATA Type [this is the setting]

In the HDD Boot Priority I have:
-SCSI-0 RAID 1
-SCSI-1 WD 500 HDD (the standalone)
-USB HDD (FD happened to be plugged in)
-Bootable add in cards

So it appears I could have the Boot priority go to the single HDD looking for the boot instructions - it just isn't labeled as a SATA. Don't know if W7 will like that or not.

Off course that's the easiest way gregrocker. But:

-one disk with "boot manager" and windows 7 (that's why I adviced him to disconnect the other drive)
-other disk with winxp bootmanager and working as before

This is what you advice. and that's what I want him to do as well.
but later: adding winxp to win7 bootmenu only adds an entry in bootmenu which starts winxp on the other disk. Disconnecting windows7 disk .... winxp will start without problems.

This is true, as well.

XP will only hold the System boot files if Win7 is installed last and places its boot files on the XP partition to autoconfigure a Dual Boot, as it does if XP HD remains plugged in.

kaktussoft: your outline of steps was how I was going to try to proceed (my concerns about AHCI aside - the standalone drive works fine now).

Thank you and gregrocker for the advice. Will report on outcome...

I should have clarified intent a bit more:

Once past the W7 install (with the RAID disconnected) and having a reasonably operating system, I intended to leave Drive 1 (with Win7) as the first bootable device, then modify its boot manager/loader to allow for boot to WinXP on Drive 0 (BCDEdit seems to readily allow for this). My plan is to use W7 for some gaming purposes (at the moment) and I will likely keep using XP for bulk of PC use.

Thank you both.