SATA 2 PCI controllers

SATA 2

— the presence of at least one SATA 2 connector on the controller board.

Initially, the SATA standard was developed for connecting internal drives, primarily hard drives (HDD). Specifically, the SATA 2 version provides speeds up to 300 Mbps (2.4 Gbps). This is generally enough for individual hard drives, but for RAID it is already not enough, not to mention high-speed SSD — especially since there is a faster version of this interface, SATA 3. So controllers with SATA 2 are almost out of use today.