It is possible, in many cases, to install and run XP on a system
that originally shipped with Windows Vista.
1. About 2 hours to perform all necessary tasks.
2. A Windows XP CD. With valid key, of course.
3. Basic knowledge of partitioning.
4. Basic knowledge of (re)installing XP.
5. Knowledge of what a "driver" is.
1.Before you attempt to install XP, backup any important files. Installing XP over Vista will necessitate formatting the hard drive.
2. You need to find drivers for all of your hardware. XP's driver collection was barely adequate in 2001, let alone today. A basic checklist of parts you need to find drivers for:
A. Video card (NVIDIA, ATI, Intel, S3, Matrox, etc...)
B. Sound card (Creative Labs, Intel, Realtek, etc...)
C. Ethernet controller (Intel, Broadcom, Realtek, etc...)
D. Wireless controller (Intel, Atheros, Broadcom, Realtek)
E. Motherboard chipset (Intel, Via, NVIDIA)
You can find information in Vista's Device Manager, as well as on your computer manufacturer's site. The manufacturer may (or may not) also have XP drivers for the parts available. If they do not, try to find a specification list for your model, and work backwards from that.
1. Restart your computer, and enter your BIOS. The key to enter your BIOS will probably be either Esc, F1, or Delete.
2. Check the "boot priority" and make sure that the CD / DVD-ROM drive is the first boot device.
3. If you have a SATA hard drive (most new computers do), find the setup for the SATA controller, and find an option to run it in "Legacy" or "IDE" mode. XP came out before SATA drives were produced, so it cannot use them without special drivers. Since XP does not have the drivers on the CD, you have to make the BIOS pretend the drives are actually IDE drives for now.
4. Save the changes and reboot.
5. Begin the Windows setup. This should be familiar to you.
6. Delete the current partition(s) on the hard drive, and tell it to format the drive with a new NTFS partition.
A. If you get errors like "Windows setup could not find a hard drive on your system", you have not properly set the SATA controllers to run in legacy mode.
1. After a basic XP installation is up and running, you will need to install the drivers. Install either the wireless or Ethernet driver first, depending on which method you use to connect to the internet. This is so you can A.) validate your Windows install, and B.) search for other drivers if you forgot one, or if you got the wrong one.
2. Install the other drivers.
3. Reboot your computer, and set your SATA controllers back to their normal mode. If you have installed the chipset driver correctly, XP should have no problems booting. It will also be slightly faster than leaving it in Legacy mode.
4. Reinstall your other software, as needed.
You will likely not be able to use ay of the software that came with your Vista computer. Although most of it is likely garbage, it will also include a DVD decoder for your DVD drive. XP does not come with one. You'll have to either buy one, or use a free decoder like the one that comes with VLC.