This is the second time Amazon has started taking preorders for XP. The online retailer is offering the full version of Windows XP Professional for US$299.99 and the upgrade version for US$199.99.
Microsoft has yet to reveal pricing for Windows XP but is expected to release that information any day.
"We have not yet announced pricing," said Microsoft spokesman Frank Shaw. "You can expect that (the Amazon preorder pages) won't be up there for very long."
In July, Amazon took preorders for several versions of Windows XP at similar prices. The preorder pages were quickly removed, a move sources said was prompted by pressure from the software giant. Amazon said the preorder pages were posted in error.
If Amazon's pricing mirrors Microsoft's plans, Windows XP Professional will be less expensive than Windows 2000, Microsoft's current operating system for business users. The full and upgrade versions of Windows 2000 have list prices of US$320 and US$220, respectively. A number of retailers, however, including Amazon, discount the upgrade version to US$190 and the full version to US$280.
Although Microsoft won't begin retail sales of Windows XP until October 25, consumers will be able to get their hands on it before then. Microsoft will allow PC makers to start selling Windows XP desktops and notebooks on September 24.
The software giant plans to hand off the final Windows XP code to manufacturers this week. With the final code, PC makers can start to load the operating system onto computers.
Amazon representatives could not immediately be reached for comment.
