M2formfactor

The M.2 form factor is a specification for a computer expansion card slot and connector. It is designed to replace the smaller mini-PCI and mSATA slots. M.2 allows for more versatile use of connectors and can be used for a variety of expansion cards, including Wi-Fi, Bluetooth, GPS, and solid-state drives (SSDs). The M.2 standard defines various keying types for the connector, indicated by letters such as B, M, and B+M. These keying types determine the type of interface the M.2 slot supports, with B-key typically supporting PCIe x2 and SATA, M-key supporting PCIe x4 and SATA, and B+M key supporting PCIe x2 and SATA. This allows for flexibility in motherboard and device design. M.2 slots can also be configured to support different bus interfaces, including SATA and PCI Express (PCIe). PCIe support is further categorized by the number of lanes, commonly x2 or x4. This enables M.2 SSDs to achieve significantly higher transfer speeds compared to traditional SATA SSDs. The physical dimensions of M.2 cards are also standardized, with common lengths being 30mm, 42mm, 60mm, 80mm, and 110mm. The most common size for M.2 SSDs is 2280, referring to 22mm width and 80mm length. The M.2 form factor has become widely adopted in modern laptops and desktop motherboards due to its compact size and high performance potential, especially for NVMe SSDs.