Regardless of whether you have Volume Licensing agreement with Microsoft, please stop paying Dell extra money to downgrade to Windows XP! All Windows Vista Business licenses (retail, OEM, volume) include Windows XP downgrade rights. The extra cost to Dell is for the convenience of having Windows XP preinstalled; since you are wiping the disks and installing an image, you do not need this convenience and expense.
For machines that you have already purchased with the Windows XP downgrade:
- Download Magical Jellybean Keyfinder (http://www.magicaljellybean.com/keyfinder/) and run it on each new machine with Windows XP. This extracts the factory-installed product key. It will likely not match the product key on the sticker.
- Save or write down the product key.
- Copy the file C:\dell.sdr to portable drive or network location.
- Apply your disk image to the machine.
- Copy the dell.sdr file to C:\.
- Boot and type the product key that you wrote down earlier when prompted.
For machines with Windows Vista preinstalled that you want to downgrade to Windows XP:
- Boot into Windows Vista and do all of the first-run setup steps.
- Run the Windows Vista Product Activation Wizard. (Start|Control Panel|System; click the "Change product key" link at the bottom of the page.)
[I'm not sure of the next few steps because I've never done it, and I don't want to mess with my configuration.]
- Unplug your network cable and disable wireless networking so that you have no network connectivity.
- Try to find an option to activate via telephone.
- Call the number that is provided, and tell the operator that you want to downgrade. You'll have to provide the product key from the sticker. The operator will provide you with a new product key or will reset the one on the sticker so that it works with XP.
- Reconnect to the network, if applicable.
- Install your image, and type the product key provided by the operator when prompted.
- Activate Windows when prompted.
I think that Windows XP retail and OEM builds will let you install with no product key if you have integrated Service Pack 3. In that case, you can follow the above steps from within XP.
If you have a Volume License agreement with Microsoft that includes a Windows Client license upgrade of either XP or Vista, you have access to the volume license media for Windows XP on the eOpen or MVLS websites. Download the CD image, burn it, and use it for your image. Then you can use your volume license key and skip all of the activation and product key problems. This is specifically allowed by Microsoft for any licensed copy of Windows XP and Vista, not just those licenses purchased on the agreement. (See this document on this page: http://www.microsoft.com/licensing/about-licensing/volume-licensing-briefs.aspx.)