I would boot to the Windows XP CD and install from there onto the second hard drive. Just keep in mind that installing Windows XP after Vista is installed can render Vista unbootable since the XP boot loader would override that of Vista. If this happens you can, however, resolve the issue by following these instructions.
Once it is properly configured, each time you boot you will be prompted to select an operating system, be it Vista or an 'earlier edition.' If you do not make a selection within 30 seconds Vista will be selected automatically.
Hope this helps,
John
I am about to order a new Vista system from Dell. Because I know that some of the software that I use regularly isn't yet Vista compliant (but I desperately need a new computer and want Vista pre-installed) I am planning to install a second drive into the new PC and do a clean Windows XP install on the second drive for dual-booting. I'm just wonding if there's anything I should know before I even order the computer and/or before I install the second drive and XP. I have no experience with setting up or using dual-boot systems so any suggestions/advice would be appreciated.
The only specific question I can think to ask at this point is: Should I be booted into Vista when I insert the XP CD to begin the XP installation or should I boot to the XP CD?
Thanks.

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