The Xbox Series X may have expandable storage, but the problem is that you can't use your old storage on the new Xbox console. And that could come at a rather large price.

As reported by Digital Foundry (via USGamer), the Xbox Series X uses a proprietary NVMe SSD design in the expansion slot. It's a clever design that is easy to install, has a built-in heatsink, and is compatible with the new Xbox's Velocity architecture. However, Microsoft is the only supplier of this cartridge-based SSD, which is manufactured by Seagate, a well-known hard drive manufacturer.

For those unfamiliar with the term NVMe, it stands for Non-Volatile Memory express, a solid state drive (SSD) communication standard developed by a consortium of SSD manufacturers. such as those found in PCs and gaming consoles. It is faster than a regular SATA connection and allows for faster data read/write speeds.

The inclusion of these custom SSDs is an improvement over the Xbox One, which only works with external hard drives. Additionally, the cartridge-style design means that SSDs can be easily swapped between SSDs and data can be transferred between consoles.

The Series X can still use a traditional external hard drive, but it will not have the advantages offered by a cartridge SSD. Also, it is not possible to play Series X game saves on existing drives unless the data is stored on an internal SSD or cartridge SSD.

Pricing for these cards has not yet been announced, but an educated guess does not paint a very good picture. Currently, a 1TB NVME Seagate SSD costs about $199, so the Series X expansion drives, being proprietary, will no doubt cost $200 or more per unit.