It also gave a first look at the console's unusual new design at the Game Awards. The cube-shaped box looks a little like a PC tower, rather than a traditional console.
It is able to be used either lying down or standing up, the company said.
The new console also has a redesigned controller, Microsoft said, though it looked largely similar. It has a new share button, allowing people to more easily post screenshots and videos, as well as having a new "size and shape" to make it able to "accommodate an even wider range of people".
That controller will come with every Xbox Series X and will be compatible with the current Xbox One and PCs, Microsoft said.
The Xbox will come out in the holiday period in 2020, at roughly the same time as the PlayStation 5.
Microsoft has revealed some information about the console, which has until now been known under the codename "Project Scarlett". The reveal is the first time that the name of the console has been confirmed, as well as its release date.
It did not give any more information about the specs, only stressing the previous information it had already announced.
Microsoft pointed to "orld-class visuals in 4K at 60FPS, with possibility of up to 120FPS, including support for Variable Refresh Rate (VRR), and 8K capability". It said the console would be "powered by our custom-designed processor leveraging the latest Zen 2 and next generation RDNA architecture from our partners at AMD, Xbox Series X will deliver hardware accelerated ray tracing and a new level of performance never before seen in a console".
It also confirmed once again that the new Xbox will be able to play old Xbox games and use the old console's accessories.