When console game developers show off their games, it's not surprising to learn that they are running on development kits instead of the actual consoles themselves. So when Microsoft decided to show off the latest Xbox One games, one could reasonably expect that they won't be running on actual Xbox One consoles but on development kits with comparable specifications. However, it seems that this was not the case at E3.
According to Julian Rignall from US Gamers:
I just played an Xbox One game using an Xbox One controller that crashed... to a Windows 7, Hewlet Packard-branded desktop. Magic!— Julian Rignall (@JazRignall) June 13, 2013
And then the above image surfaced on HFBoards along with this other one, which quite clearly shows that the machines in the demo cabinets were systems running on Windows 7 and with NVIDIA graphics cards, and by the looks of it, something from their new GeForce GTX 700 series - which means either the GeForce GTX 780 or GeForce GTX 770, very powerful high-end cards.
This is an embarrassment for not only Microsoft but also AMD because the new Xbox One is said to be running a Windows 8 kernel and also utilizes AMD hardware. The 8-core CPU is based on AMD's latest "Jaguar" architecture while the graphics is based on AMD's latest GCN architecture and is said to have 768 cores.