"To upgrade the machine" means to improve or enhance the capabilities or performance of a device, usually by installing new or more advanced components, software, or hardware. Full definition
You can't upgrade a machine and roll back and keep the key to do a clean install on another computer. (howtogeek.com)
The crafting menu gives you a ton of options, especially if you build the various upgrade machines that give you access to an increasing number of items to craft. (egmr.net)
This means that pro users will be able to swap out graphics cards, hard drives, and the like to fully customize and upgrade their machine after purchase. (imore.com)