I was able to do some research and according to the manufacturer this PCIe card is compatible with the following systems: - Linux Kernel 3.3 or above - Windows 7/7-64/8.1/8.1-64/10/10-64 - PC with one free PCI Express x16 / x32 slot If one of these OS is used, it should also be installed in a NAS, otherwise I can well imagine that it will not be recognised or will only work to a limited extent. Unfortunately, the manufacturer does not provide any information regarding RAID, I assume that this is not a RAID controller. The following would be a card with RAID, but 4 drives instead of 5: Delock storage controller (RAID) Unfortunately I could not find a suitable model with 5x slots.

No, because the M.2 slots here are Key-B and the 980 Pro Key-M. This means that it does not fit.

Yes.