M.2 SSDs

Which M.2 drive fits a Dell BOSS card

Every Dell BOSS card takes 80 mm M.2 drives, and the interface depends on the card:

M.2 lengths, keys and interfaces for servers

An M.2 drive is identified by width and length, so a 2280 drive is 22 mm wide and 80 mm long, and Seagate's NVMe primer lists 42, 80 and 110 mm as the common lengths. The edge connector is keyed for the interface, SATA (socket 2) or PCIe x4 (socket 3), which is why an NVMe stick does not run on a SATA-only card even when the length matches.

Boot pairs: Dell BOSS and HPE NS204i

Both server makers build the boot device as a mirrored pair outside the data bays. Dell describes BOSS-N1 as a RAID solution for booting, and HPE describes its NS204i boot devices as a dedicated hardware RAID 1 solution that keeps the OS separate from data, creates the RAID 1 volume automatically and leaves every drive bay open for data; the NS204i-u version for Gen11 servers is a hot-plug unit with two 480GB M.2 NVMe drives. Browse BOSS controller cards, and see our Dell BOSS card guide for which PowerEdge servers take each card. For 2.5-inch drives, see SATA SSDs and NVMe SSDs, or every server SSD.

Used M.2 SSD questions

Which M.2 drives work in a Dell BOSS card?

80 mm (2280) drives of the card's interface. Dell's user guides specify two 80 mm M.2 SATA SSDs for the BOSS-S1 and BOSS-S2, at 6Gb/s on the S2, and, for the BOSS-N1, 80 mm M.2 NVMe SSDs linked over PCIe Gen3 x4. A 110 mm drive will not fit these cards, and an NVMe stick will not run on the SATA versions.

SATA or NVMe M.2 for a server boot drive?

Use the interface your boot card takes. Dell's BOSS-S1 and BOSS-S2 run M.2 SATA, while the BOSS-N1 and HPE's NS204i boot devices run M.2 NVMe. NVMe is the faster link: Seagate notes that SATA is limited to 600 MB/s, while PCIe Gen3 x4 offers up to 3,000 MB/s. Either way, buy the pair as matched drives so the mirror stays balanced.