After installing Windows XP on my F500 laptop I decided to take the next step and make the machine dual bootable. My rationale for doing so was that, although I prefer Windows XP to Vista, I did not want to give up easy access to the only copy of Vista currently available to me. Also, a dual booting machine gives me additional inherent flexibility and redundancy that a single OS machine does not have. And since the Vista partition is seen as a 2nd disk by XP (and vice versa), little disk space is actually lost and sharing files between both OSes becomes trivial.
After considering several options, I decided to use Vista's boot loader as the vehicle to select which OS to use, and I also elected to install the dual boot setup on the original hard drive which came with the machine. Since we had previously loaded a copy of Windows XP onto another disk, I elected to use that load instead of installing XP from scratch all over again. If your situation is different, you'll have to modify these notes accordingly. Here are the series of steps we went through to make this work:
Before making any changes to a disk with critical data on it, please make a backup. We used Norton Ghost to backup the entire F500 hard drive (both the active and recovery partitions) onto a separate drive before making any changes. Whatever method you use, make sure you are comfortable with the restore procedure before making changes to the original disk.
Initially, we tried using Partition Magic to carve out some space for XP, but we discovered that our version of Partition Magic did not seem to like the Vista partition. Perhaps we need to buy a new version of Partition Magic, but we worked around the problem by using Vista's own builtin tools to resize its active partition, and it worked reasonably well. Here's the basic procedure:
Go to Computer -> Right Click -> Manage -> Disk Management -> Select a Drive -> Shrink Volume.
Select the amount of free space you desire for the XP partition. Note that there are some Vista system files (restore points, swap files, etc.) that cannot be moved while Vista is runing and thus there is a limit on the amount of space that can be reclaimed using this method. We weren't able to free as much space as we originally desired, but we were able to shrink the partition to just over 1/2 its original size, and this was satisfactory for our purpose. We then used the space we just freed to create a second XP partition. We did this by right clicking on the unallocated space and selecting New simple volume. Follow the New simple volume Wizard and accept the defaults until you get to the point where you can insert "Volume label" and type XP there to make identification of your XP installation drive easy. At this point you would select the "Quick Format" to speed the process and continue with the wizard to completion of this action, if you were loading XP from scratch. However, we used a different approach.
This part was relatively painless, because the hard work of finding and loading all the right drivers had already been done. Before removing the drive on which we had initially built XP, we used Norton Ghost to back up the XP partition to another external disk. We then used Norton Ghost to import (restore) this backed up partition to the newly created partition on our dual-boot drive. Norton Ghost had no problem copying the backed up XP partition to our newly created smaller XP partition.
Next, we used EasyBCD to configure the dual boot option in the Vista boot loader. Run EasyBCD (requires UAP approval), and select Add/Remove Entries -> Add an Entry -> XP. Type the drive letter of the XP partition you just created and loaded, and name it something to denote that it is Windows XP. Finally, click on Add Entry.
Next, copy the following three files from the top level directory on the XP partition to the top level directory of the Vista partition (none of these files should exist by default on Vista): boot.ini, ntldr, and NTDETECT.COM. These are needed by the boot loader to boot XP. Depending on how you have Vista configured, you may have to go to Control Panel -> Folder Options and uncheck the Hide protected operating system files box.
After performing the above steps, upon booting the F500, you should see a screen that allows you to select either Vista or Windows XP. I made XP the default boot option (again, using EasyBCD). This default, as well as the time allowed for manually choosing which OS to boot before the boot loader arbitrarily boots the default OS, is configurable by EasyBCD.
When Vista is active, the XP partition appears as a secondary partition to Vista, and when XP is running the Vista partition is accessible in a similar fashion. This permits data to be easily shared between the two OSes.
As with any free advice, we make no warranties about its correctness or fitness of purpose for your application. We do not assume any responsibilities for any problems that may arise from attempting to follow these directions. We also have no idea if attempting this procedure will void your warranty with Compaq. We have tried to accurately represent what we did to dual boot Vista and XP on our F500 laptop, and we can only state it works for us and we're quite satisfied with the results. Good luck and good hacking!