|Getting a valid dual boot up and running is pretty complicated. Typically the people who'd attempt it have been in the industry long enough that they already have a rough idea what to do.|
A rough outline of the steps for dual booting a laptop
1) Find WinXP drivers for your laptop.
2) Add another hard drive to make room for WinXP. (Warning: Might void your warranty.)
3) Find a real copy of WinXP install CD.
4) Find a bootable copy of the Windows Recovery Environment. This might require a Windows 7 install DVD, but you can extract it to a bootable USB stick.
5) Slipstream the SATA drivers onto the CD. You might as well slipstream SP3 onto the install as well.
6) Burn a copy of your new WinXP install CD. Make sure it's bootable.
7) Boot from the new WinXP install CD. Install to new drive. You'll probably have to make a partition, but you shouldn't delete one. (If Windows says it needs to, you're installing to the wrong drive.)
8) Get your WinXP environment up and running. Install all drivers and patches.
9) Boot to the Windows Recovery Environment. Run "bootrec" with the "/FixBoot" option. You might also need to run it with the "/ScanOs" option.
10) Congratulations, you just spent a week doing something you probably didn't need to do in the first place.
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