Steve from the YouTube channel Gamers Nexus has a developer version of the Xbox Series X disassembled† He came across a 1 TB SSD, the same as in the retail Series X, but much more memory: 40 GB in total.
The Xbox Series X for consumers has to make do with 16 GB of memory. It makes sense for a devkit to have more memory; games in development are not optimized yet, and several debug programs will also be running. However, 40 GB seems very high.
Unfortunately, Steve was unable to test whether the larger memory also provides better in-game performance: the Xbox was blocked at the hardware level. Probably the previous owner of the device had tried to play online, which was detected by the Microsoft servers.
/data/photo/2022/01/30/61f6b3fe4814a.jpg "Shin Tae-yong has been crossed out, lots of Rumakiek are sought by PSSI to go to the SEA Games")