The confusion is because of the word 'interfaces'. There are two parts to using the device, how it connects between the itself and the host (motherboard in this case), and how they communicate (electronics/handshaking).
All SATA devices connect with the same cable (other than e-SATA which is a special case). The electronic/handshakes vary by version of SATA. Just like Wireless Routers, they can have A, B, G, or N speeds. Depending on router settings, you can have all computers connected to it with varying h/w speeds. Unlike SATA though, which manages each cable individually, a router will drop to the lowest speed of all devices.
Why 4 of one speed and 2 of another, probably two reasons. Many people have the older SATA i and II devices already so they'd connect it to those connections, secondly, SATA III is more expensive for the components to produce, hence motherboard costs are higher, and there are probably less devices for it now. Me, at this point in time I'd only buy a motherboard that has USB 3.0 and SATA III suport. I know I'll need it later.
Accepted Answer ·
Posted 4 years ago