By raw bandwidth:

SATA 6 Gb/s (3.0) > USB 3.0 (5 Gb/s) > SATA 3 Gb/s (2.0) > SATA 1.5 Gb/s (1.0) > USB 2.0 (480 Mb/s)

Those are the theoretical specification limits of the raw bandwidth. The actual bandwidth will be significantly lower, depending on the efficiency of the protocol used.

USB 2.0's 480 Mbit/s raw bandwidth is equal to 60 megabyte/s transfer rate, but it's normally bottlenecked to about 30 megabyte/s transfer rate because of the protocol. SATA's protocol efficiency is 80% (due to the 8b/10b data transfer protocol used) and plus some overhead, so the 3 Gbit/s is 2.4 Gbit/s actual or 300 megabyte/s, excluding additional protocol overhead. And from the SSDs, they seem to be bottlenecked to about 250+ megabyte/s instead of hitting that 300 megabyte/s ceiling.

eSATA is based on SATA 1.5 Gb/s (1.0), so it is slower than SATA 3 Gb/s (2.0).

For those interested in what the future might bring us and haven't heard of Light Peak, take a look at Light Peak.

I agree that those are specs on paper. But there is one more factor to consider, the SSD given cannot hit SATA 3 Gb/s's maximum limit, so it is the bottleneck and not USB 3.0.

But it does seem to be slower than other benchmarks of the same drive.

Thanks for the correction.

This post has been edited by everling: Feb 4 2010, 09:16 PM