Microsoft XDK has 40GB GDDR6 memory
Gamers Nexus purchased one of the Xbox Series X development kits, a special type of consoles designed specifically for game development.
The dev kit also known as XDK obtained by Gamers Nexus is a 2020 version of the development kit featuring AMD APU codenamed “Scarlett”. It is equipped with 8-core AMD Zen2 architecture CPU and RDNA “Navi” graphics processing unit with 56 Compute Units. Those specs are likely the same for the retail and development kits, but there might be changes to the clock speeds.
As confirmed by GN, the development kit that was torn down features not 16GB of GDDR6 memory but 40GB, which might have been the reason why early Xbox Series X leaks have mentioned higher capacity at some point before the console was released.
The XDK is equipped with 40GB of Samsung GDDR6 memory clocked at 14 Gbps. It is unclear if the memory is divided like on the retail unit, which has three pools for graphics (10GB @ 320-bit), system memory (3.5GB @ 192-bit) and the operating system (2.5GB @ 192-bit).
The larger memory capacity is typically used for debugging, frame data analysis or verbose logs. Developers can also use this memory to decompress game builds rather than resource overhead for pre-optimized games, one of the game developers explains in the video comment section.
The Xbox Series Development Kit is available on eBay for around 1350 EUR, but this price is only for the pre-banned version. Microsoft is well aware about the illegal sale of their consoles and is making sure that those devices no longer work, even for offline games, which is why it is crucial not to connect these devices to the Internet. The sample purchased by GN was already pre-banned, so it cannot be used for any gaming activity.