SATA 6

seekermeister · 15 Sep 2010

I touched on this topic in another thread recently, and I understand that for the most part that SATA 6 probably has no real effect on hard drive performance, partly due to the lack of SATA 6 support on most motherboards...including the one that I have.

However, I got to wondering if the same would be true with SATA 6 hard drives connected externally via a SATA 6 controller card, either in transfers between these external drives, or possibly between an internal and external drive, since the controller "might" suppliment the motherboard's limitations?

pparks1 · 15 Sep 2010

Sata 6.0Gbps is no real benefit, as a mechanical hard drive can only move data at 120MB/sec or less. Since that isn't even coming close to saturating the Sata 3.0Gbps interface...it's really pointless to getting a faster interface. Until you get a faster hard drive that is going beyond the SATA 3.0Gbps interface (only a couple of SSD drives even knock on that door)...there won't be any real performance gains.

seekermeister · 15 Sep 2010

I expected that would be your answer, and I don't really question it...except your phrase "there won't be any real performance gains." What does "REAL" mean? A marginal difference, or none at all? If no hard drive of that speed is capable of any improvement, regardless of a rig's configuration, then I feel that to label a hard drive in this manner is fraudulent. Despite the fact that there probably is no improvement at all, I keep getting a nagging notion that I should see a SLIGHT difference in performance, when all of the hardware involved is SATA 6 compatible.

EDIT: Another thought occurred...you say that no hard drive of this sort can move data in excess of 120MB/s, but I have seen raid systems using such drives with higher performance speeds.

pparks1 · 15 Sep 2010

I would count on no change.

Drives and interfaces have always had far greater theoretical limits than real world performance for years and years. Most mechanical hard drives still aren't completely saturating SATA 150 (1.5Gbps), let alone Sata 3.0Gbps, and then Sata 6.0Gbps.

The small amount of difference you would see would most likely revolve around NCQ tweaks and such....but I'd bet dollars to donuts that you couldn't quantify it with a stop watch when you booted up your computer, launched your favorite apps and then shut down the computer once again.

Your biggest gain might be from a 16 or 32MB cache on the older drive, to a 64MB cache on the newer drive...but that has nothing to do with it being a SATA 6.0Gbps drive.

Labeling a drive like this is not fradulent. It's simply describing the interface specifics and the theoretical limits. It's not telling you how fast the drive actually is....just what the components are capable of. So, the interface is capable of 6.0Gbps...but the other components aren't there yet.

seekermeister · 15 Sep 2010

As said, I have understood that hard drives weren't obtaining their rated SATA performance, but I thought that eventually with other hardware improvements that they might at least do better than they are. If it will never be possible to benefit from a higher rating drive, then someone should start a class action lawsuit.

EDIT: I overlooked your last sentence

Labeling a drive like this is not fradulent. It's simply describing the interface specifics and the theoretical limits. It's not telling you how fast the drive actually is....just what the components are capable of. So, the interface is capable of 6.0Gbps...but the other components aren't there yet.

Until now. Theory is not what anyone buys. You mention whether the other components are there or not. I assume that you are referring to those outside of the drive itself. If so, this goes back to my original question, which is based on the idea that ALL components are SATA 6 and present. Thus, is the limitation actually within the drive itself, or in the environment in which it operates?

pparks1 · 15 Sep 2010

Here is a breakdown of the fastest drives out there
Benchmark Results: Throughput : VelociRaptor Returns: 6Gb/s, 600GB, And 10,000 RPM

Considering that SATA 3.0Gbps tops out at approx 300MB/s....and the fastest mechanical hard drive is only 1/2 that fast.....you can form your own conclusion.

seekermeister · 15 Sep 2010

Those charts are clear enough...except that they don't specify the hardware that they are tested on, and it seems that would be a factor in determining performance. I did notice that a couple of hard drives inched over SATA I performance, such as the Samsung Spinpoint F3, but that was only on the maximum throughput, so it is obvious that it couldn't maintain that speed overall. While the chart did include my WD1001FALS, I wish it had included my WD1002FAEXs also, though I doubt there would be any real difference, yet the performance that I measured with HD Tune is slightly better than they so, even with my old hardware.

pparks1 · 15 Sep 2010

Yeah, it's so tough to really evaluate any of this stuff. I think lots of people expect "big", "noticeable" changes since 6.0Gbps is over 2x that of 3.0Gbps. But I think in all reality, the difference would likely be around 2% at most....which I think would disappoint most people.

I think the hard thing for people too is that they often replace an older system with a newer system and rave about how fast it is. But that's obviously dependent on the CPU, RAM, hard drive, controller, drivers, chipsets, etc. Or like I said before, a doubling of cache could cause a small 2% change...but it's relevant regardless of the interface.

seekermeister · 15 Sep 2010

I've never expected a big change in performance, but I do expect some, if there are no bottlenecks caused by other hardware. Case in point...transferring data between two SATA 6 hard drives connected to the same SATA 6 controller. Considering how bad the current performance is at times, the theoretical limits is not even a faint hope, but when transferring between 10 & 50MB/s, which doesn't even come close to even SATA I performance, one would think that something better is possible.