Microsoft charges for OEM licenses. PC manufacturers, however, will include other software with Windows for a fee (e.g. Imagine Adobe pays Dell for Adobe Reader to be included on Dell consumer systems).
It is also plausible that Microsoft has a patent agreement with PC manufacturers so that they have to pay Microsoft a fee to ship systems with Linux installed. I know we've seen similar situations with companies that run Linux servers or sell Android devices.
It is also plausible that Microsoft has a patent agreement with PC manufacturers so that they have to pay Microsoft a fee to ship systems with Linux installed. I know we've seen similar situations with companies that run Linux servers or sell Android devices.