Every single laptop and any prebuilt computer I find in the market comes pre installed with a Windows.
A good friend approached me to install a Linux on a brand new machine and just to make sure we called the customer support line, informing there was interest to return the windows license, as the software would not be used.
The reply we got was that by removing the software the warranty of the equipment would be null and void. The option was to ship the computer to their maintenance provider and have it removed, with costs presented at end for labour.