For Surface Pro 3, it is possible to perform a clean install of Windows 10 through the use of a downloaded recovery image. This will put your device into the same state as it would be in when purchased new with Windows 10 installed.
Until the free Windows 10 upgrade offer ends on July 29th, 2016 you can use the Windows 10 recovery image on a Surface Pro 3 that has never had Windows 10 installed and it will activate using the product key that came with the device. After July 29th, 2016 the Windows 10 recovery image will only activate on devices that came with Windows 10 or had previously installed and activated Windows 10.
To use the recovery image:
- Go to the Download a recovery image for your Surface page and select your product.
- You should see the original Windows 8 image that shipped with your Surface, as well the new Windows 10 Version 1511 image.
- Click Download and follow the rest of the steps to create the Windows 10 recovery drive and use it to reset Surface.
- For more detailed information, see our Restore or reset Surface article.
Hope this helps,
Greg