: Standard inclusion of Ethernet (RJ-45), USB 2.0, and occasionally USB 3.0.
Typically includes one PCI Express 2.0 x16 slot for dedicated graphics and may include additional PCIe x1 slots depending on the exact form factor. Storage: SATA 3.0 Gb/s and SATA 6.0 Gb/s ports. intel desktop board 21 b6 e1 e2 specification link
"21 B6 E1 E2" is not a motherboard model name, but rather a regulatory or industry specification marking found on several different Intel boards from the early 2010s. It is most commonly associated with boards using the LGA 1155 socket : Standard inclusion of Ethernet (RJ-45), USB 2