What's the difference between a SATA and a SATA II?

Question

I've heard about both, but how are they different? Is the SATA slower? If so, is it because of the cache size? I saw a SATA II advertised but when I went to look at the specs, it had dropped the II and was now a SATA so I now I'm confused. If it's all in the cache, then I understand, if not, I'm really confused.

Answer 1

SATA has a theoretical maximum transfer rate of 150MB/s

SATA2 (or SATA/300) = 300 MB/s

It is the handshake between the drive's circuit board and the controller's chipset. Both must be SATA2 to get SATA2 performance, but either can be backward-compatible.

It's not the cache. One other thing that may be more common on SATA2 is "native command queueing", further closing the gap between ATA and SCSI performance. To see if a specific drive supports NCQ, read the spec's on the drive.

Answer 2

In 2002, Serial ATA (SATA) was introduced as the next step in ATA technology. SATA provides greater scalability, simpler installation, thinner cabling and faster performance (up to 3.0 GB/s). SATA also maintains backward compatibility with Parallel ATA drivers.The entire desktop market has started moving towards the SATA interface from the more traditional Parallel ATA interface.

The first step toward a better understanding of SATA is to know that SATA II is not the brand name for SATA’s 3Gb/s data transfer rate, but the name of the organization formed to author the SATA specifications. The group has since changed names, to the Serial ATA International Organization, or SATA-IO.

The 3Gb/s capability is just one of many defined by the former SATA II committee, but because it is among the most prominent features, 3Gb/s has become synonymous with SATA II. Hence, the source of the confusion.