Having got a friendly email from Crucial that there is new firmware for my 512Gb M4 SSD in my Mac Pro, I gaily started on the process, outlined here ...

Samsung has released new firmware for its latest and greatest SSD, and owners should probably install it ASAP. The Samsung 990 Pro SSD has a reliability problem, and this firmware update appears ...

It upgrades firmware in 3,1 Mac Pro towers and later so they can boot MacOS from an NVME drive at speed. Some later Mac Pros already have this apparently.