The M.2 slot on the 8940 is Gen 3 and the Crucial Gen 4 SSD you listed would run at Gen 3 speeds not Gen 4. In that instance you may as well save a few dollars and install an M.2 Gen 3 SSD which will still run in the 3600 MB/s range. To be honest the speed difference of a Gen 3 to a Gen 4 may seem quite noticeable but for everyday use the average user probably could not tell the difference. This YouTube video touches on that subject.
Dell XPS 8940 i9-11900k @ 3.50GHz According to the Crucial site the following 2TB drive is compatible. Could somebody confirm, deny or tell me the extra speed will not be used and I am wasting my time. Crucial P5 Plus 2TB PCIe M.2 2280SS Gaming SSDCT2000P5PSSD8Configuration ID: CT202090152TB M.2 (2280) Single-Sided SSD • PCIe NVMe Gen 5 • 6,600 MB/s Read, 5,000 MB/s Write Thanks.
XPS 8940, 2TB SSD upgrade