Most mobo's have supported 6Gb/s for the past 5+ years - SATA III was released in 2009. I would be surprised if you have a running motherboard on a not-intentio

Most mobo's have supported 6Gb/s for the past 5+ years - SATA III was released in 2009. I would be surprised if you have a running motherboard on a not-intentionally-retro computer without SATAIII; My ancient gaming machine (now a fileserver)from 2012 has all ports SATAIII and is capable of achieving those speeds.