Apparently a Durango or as we commonly know it as an Xbox 720 Development Kit was leaked for sale online. Apparently Digital Foundry has been in contact with the person selling it and a few development teams and it seems to be genuine. It was being sold for around $10,000 on-line and it appears to be just a normal PC Tower running the software. From what I've read and found out it has an nVidia GPU and more than 8GBs of RAM. It also has an 8 core CPU and is designed to run 64bit Direct X 11 Games. This may or may not be the final specifications, since development kits are usually a place-holder and designed to give you a rough idea of what to expect.