Microsoft has began taking orders for the $14.99 Windows 8 upgrade promised to customers who purchased a new Windows 7-powered PC in the last 11 weeks.

PC Users who bought an eligible Windows 7 machine after June 1 can now file an online form to queue up for the Oct. 26 delivery of the upgrade.

The upgrade to Windows 8 Pro is not free as it costs $14.99 - more than in past cycles when they were often free - but less than the $39.99 for users who upgrade older systems to the new operating system.

Registration opened today but orders will not be fulfilled until Windows 8's on-sale date of Oct. 26, Microsoft said.

PC users who qualify for the $14.99 deal must provide Microsoft with name, email address, phone number, the date of purchase, the retailer, the PC brand and model, and in some cases, the 25-character Windows 7 product key associated with the PC.

The second Windows 8 upgrade offer is a $39.99 upgrade to Windows 8 Pro for owners of older Windows XP and Vista PCs, and Windows 7 machines ineligible for the less-expensive upgrade. This one is not available yet.