It means that the Vole is dead keen to get people to upgrade to its new software, particularly as it is asking them to sign up to some fairly radical style changes.
This version will take some getting used to, particularly with the Metro user interface .
The deal will kick off on the day Windows 8 comes out and offers the most advanced retail version of the new OS, Windows 8 Pro, as the upgrade.
Most analysts expect the company to debut its newest Windows in Autumn. The company should be getting around to making its release to manufacturing, or RTM, milestone later this month.
Four weeks ago Microsoft said it would sell a $14.99 upgrade to Windows 8 Pro to buyers of new PCs equipped with Windows 7.
For $39.99 you will have a download of Windows 8 Pro. If you want the upgrade on a DVD in a nice box it will be on sale for $69.99.
This is $10 less than Microsoft charged for a Windows 7 upgrade three years ago. It is still more expensive than the Apple OS, but that is because Microsoft sells software, whereas Apple sells a hardware and software package.
Microsoft is in the position that it has to encourage people to buy new PCs so it can make more money, but if is too cheap the company will find itself out of pocket.