SATA II Doesn't Mean 3Gbps
According to the official document from the Serial ATA International Organization (SATA-IO), the term SATA II has grown in popularity as the moniker for the SATA 3Gb/s data transfer rate, causing great confusion with customers because, quite simply, it's a misnomer.
Simply put, SATA II is the name of the organization formed to develop, manage and adopt the SATA specifications.
SATA II is NOT the brand name for SATA's 3Gb/s data transfer rate.
So, do not use SATA II to represent 3Gb/s or 3Gbps.
See below for an accurate description of SATA capabilities:
For details, visit: Serial ATA International Organization (SATA-IO)