The Xbox One can actually support up to two 256GB or larger USB. Microsoft's only caveats for what the Xbox One will support is that it has to be at least 256GB in size and be USB 3.0 compatible.
The Xbox Series X ships with a 1TB internal SSD. theres 256mb memory card for the arcade, 20gighdd for the normal 360, and 120gighdd for the elite No matter what size the hdd is 500GB, 1TB etc, thry never show full as 500GB or 1TB due to system information being stored on them. In reply to BigTime Awesome's post on August 19, 2019.
