2006-08-24 14:51:57

by Marc Perkel

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Subject: SATA 150 vs SATA 300

Another speed related question. How much faster are SATA II drives
compared to regular SATA drives in real life? And - does NCQ really
help? I'm just looking for a general guess in the form of, "The Disk IO
upgrading to SATA II with NCQ will generally be X% faster." What value is X?


2006-08-25 02:32:46

by Jeff Garzik

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Subject: Re: SATA 150 vs SATA 300

Marc Perkel wrote:
> Another speed related question. How much faster are SATA II drives
> compared to regular SATA drives in real life? And - does NCQ really
> help? I'm just looking for a general guess in the form of, "The Disk IO
> upgrading to SATA II with NCQ will generally be X% faster." What value
> is X?

SATA 150 and SATA 300 refers to interface speed (1.5Gbps or 3Gbps).
Unless its entirely flash-based or RAM-based, it is highly unlikely that
your disk max out the SATA cable bandwidth.

There is "SATA II is x times faster" rule, because it depends on the
drive mechanics inside. A SATA II drive may be exactly the same speed
as SATA I, except that it is upgraded to support NCQ and other SATA II
features.

NCQ definitely helps.

Jeff