Raspberry Pi Compute Module 4: Engineer demonstrates that 128 GB of storage is possible on the tiny single-board computer
The Raspberry Pi Compute Module 4 (CM4) offers better performance than the Raspberry Pi 4 Model B and comes with built-in eMMC storage. However, the Raspberry Pi Foundation only offers the CM4 with 8 GB, 16 GB of 32 GB of storage, which is not much of a range to choose from, in our opinion.
Ivan Kuleshov, a systems engineer, has managed to install a 128 GB module though, bypassing the need to use a microSD card for more storage. According to Kuleshov, the larger eMMC module delivers up to 70 Mbps sequential write speeds and 80 sequential read speeds, or about double what a microSD card can do in a Raspberry Pi.
According to Tom's Hardware, Kuleshov used a Toshiba THGBMHT0C8LBAIG, which can be picked up for under US$45. The shortage of CM4 units with 8 GB of RAM has also led Kuleshov to use an 8 GB module from a Raspberry Pi 4 Model B. Unsurprisingly, we would not recommend upgrading the RAM or storage on your CM4 unless you know what you are doing, as Kuleshov evidently does.