Dell computers with WinXP

There’re some decent deals on Dell desktops with WinXP option at http://www.dell.com/content/products/productdetails.aspx/desktop-vostro-220st?c=us&cs=04&l=en&s=bsd&dgc=EM&cid=41048&lid=1057085 and on Dell laptops with WinXP option at http://www.dell.com/content/products/productdetails.aspx/vostronb_1510?c=us&cs=04&l=en&s=bsd&dgc=EM&cid=41048&lid=1057084. I find it interesting the WinXP option is $99 extra on most of these and included in the price on just a couple of the laptops.