lsepolis123 wrote:
You say SSD NVMe is not upgradable, but well here:
Note: Although the chips are replaced in this video rather than the whole NVMe, I think NVMe is upgradable as it can be removed from the Mac Mini M4 Motherboard... Well?
It is not upgradable in any practical sense.
Like other Apple Silicon Macs, and like Intel-based Macs with T2 security chips, the M4 and M4 Pro Mac minis do not use standard M.2 SSDs. The Apple Silicon chip (M4 or M4 Pro) contains the SSD controller, and what's on the circuit board is raw flash storage. The M4 or M4 Pro chip will be encrypting and decrypting most of the contents of the flash storage in real time. Even If you could buy a replacement board, you would need the help of another Mac to reset the one that you operated on after the upgrade. Without this reset, the upgraded computer would be an unusable "brick."
The only Apple Silicon Macs for which Apple sells "retail" SSD upgrade kits are the M2 Ultra Mac Pros. One of the kits for those will set you back $1000 USD for 2 TB, $1600 USD for 4 TB, or $2800 USD for 8 TB. (That is just for the parts and does not include installation.)
Apple 4TB SSD Upgrade Kit for Mac Pro
Maybe you could order similar parts for Mac Studios and M4 Mac minis via Apple's Self Service Repair Program – but at those prices, I bet your interest in doing so would evaporate quickly.
Either order your Mac mini with more internal SSD storage, or plan on using external SSDs.