Is A SATA 3Gb/s Platform Still Worth Upgrading With An SSD?

Even With SATA 3Gb/s, An SSD Makes Sense

If you go by the synthetic benchmarks most reviewers like to run (stuff like AS-SSD, CrystalDiskMark, PCMark 7, and Iometer), then a 6 Gb/s SATA connection appears imperative for getting the most out of today's drives. In certain cases where you're pushing a ton of data sequentially, that's absolutely the case. However, those same tests aren't very good at conveying the "feel" of a machine recently upgraded from conventional to solid-state storage. Moreover, they make it look like you really need a modern platform to take advantage of a modern SSD. Our real-world metrics demonstrate that those theoretical differences aren't always practical, though. In most cases, a SATA 3Gb/s-attached Samsung 840 Pro is almost as fast as the same drive connected to a 6 Gb/s link.

Almost No Advantages for SATA 6 Gb/s On A Typical Desktop

The 840 Pro soared in our synthetic tests when we had it hooked up to a 6 Gb/s port. It also fell flat several times when we hamstrung it using SATA 3Gb/s. When we specifically targeted sequential reads and writes, along with random I/O at high queue depths, the differences were especially pronounced. But once we started through our handful of real-world tasks, booting up and shutting down Windows 8, and loading a number of applications, the differences shrank to almost nothing. The deltas we did measure wouldn't be perceptible during your day-to-day grind.

Because the synthetic benchmarks deliberately push workloads designed to flesh out the differences between extremely-fast devices, but are seldom seen in a desktop environment, they don't correlate to the more common tasks you perform. Random I/O is important to measure, but there's a fair chance that you'll never see a queue depth of 32. And while we enjoy clocking peak sequential transfer rates like quarter-mile drag races, it's pretty uncommon to move large media files between two storage devices that wouldn't bottleneck each other. If you do copy an ISO, for example, from one SSD to another, you'll get a nice boost from SATA 6Gb/s connectivity. But if you're moving the same file from an SSD to a conventional disk, the fastest interface in the world won't help overcome the spinning media's limitations.

The Three Most Important Things: I/O, I/O, and I/O

Random I/O performance is very important from a practical point of view. Under Windows, most I/O operations occur at low queue depths. In such a situation, our synthetic benchmarks show us that there's not much difference between SATA 6Gb/s and 3Gb/s. There’s barely even a theoretical performance gap at a queue depth of one, and certainly no practical difference.

We can now answer the question of whether you need available SATA 6Gb/s ports to justify an SSD upgrade. Clearly, you're still going to see plenty of benefit from solid-state storage, even if you're using a 3 Gb/s connector. In the real world, a 3 Gb/s interface doesn't bottleneck common applications. It's only when you push the technology's limits using synthetic benchmarks, server/workstation-oriented workloads, or large SSD-to-SSD transfers that 6 Gb/s signaling kicks into gear.

The real key is getting an SSD into your machine. Just have a look at what happens when our 840 Pro goes up against the fastest desktop hard drive we've ever benchmarked, Western Digital's ValociRaptor. The disk didn't stand a chance in any of our synthetic or real-world tests.

Create a new thread in the US Reviews comments forum about this subject
This thread is closed for comments
78 comments
    Your comment
  • Combat Wombat
    Far Out! I didnt realise there was such a big difference between my Raptor, and a Samsung's 840,

    Thanks toms, Samsung will get a few hundred out of me next pay day. :P
    9
  • nukemaster
    I have been using an M4(on SATA 3gigabit/sec) on my older media center as a boot drive and for some games. The difference from the hard drive it replaced was massive. The old hard drive is still great for storing media and files.
    8
  • DarkSable
    This... was a kind of stupid test. Of COURSE an SSD is a good thing even on a SATA II connection.

    Does Tom's not remember the early days of SSDs, when everyone wanted one and noone could afford one? There was no such thing as SATA III back then, and if SSDs didn't give a benefit, nobody would have payed attention with how expensive they were.
    -14
  • LordConrad
    Quote:
    Even With SATA 3Gb/s, An SSD Makes Sense

    I could've told you that. I put a OCZ Vertex 2 in my HP dv6t-2100 laptop a while ago and the difference was like night and day. SATA II is definitely SSD worthy!
    4
  • Onus
    This article measured what was intuitively obvious. My primary system's boot drive is a 3Gb/s mSATA Crucial M4; I've felt no need to upgrade. Just today I put a 128GB 6 Gb/s SSD on an old 790GX board, and the difference is amazing.
    3
  • rdc85
    IMO It well worth it, if u had the budget... (even it in sata2 mode)

    still the price is the issue...
    hope the price will continue to decline, so it became affordable for (most of) everyone....
    -1
  • CommentariesAnd More
    Yes it is
    -4
  • jimmysmitty
    Combat WombatFar Out! I didnt realise there was such a big difference between my Raptor, and a Samsung's 840,Thanks toms, Samsung will get a few hundred out of me next pay day.


    Any SSD on 3Gb/s kill Raptors outright. Even my older X25-M does due to the sheer IOPS compared to a Raptor or any mechanical HDD.

    I do need to upgrade but not for the speed, mostly for size. 80GB is not enough even for OS and a few apps. I have messed with everything from a SATA II SSD to a PCIe SSD (Revo 3) and as long as you are on SATA II or better its going to be more than fast enough.

    But that said, I might just wait for Broadwell and SATA Express.
    1
  • mayankleoboy1
    1. This test feels kind of incomplete. What i felt was the right comparison was to add a native SATA2 SSD on a SATA2 port, and then compare it to a SATA3 drive on a SATA2 port.

    2. The startup and shutdown times will increase once you start adding softwares to the system. Specially, an Antivirus (kaspersky internet security) makes me weep on startup on a mechanical disc.

    3. Kind of stupid question : Will overclocking the CPU improve the startup/shutdown times, now that the storage bottleneck is largely removed ?

    4. Can we have the time taken by each system to install all the Windows updates, just after the fresh install ?
    -11
  • coolbz
    DarkSableThis... was a kind of stupid test. Of COURSE an SSD is a good thing even on a SATA II connection.Does Tom's not remember the early days of SSDs, when everyone wanted one and noone could afford one? There was no such thing as SATA III back then, and if SSDs didn't give a benefit, nobody would have payed attention with how expensive they were.


    This article does give very important guideline, where people evaluate different upgrade options. Conclusion is, you don't need to replace a SATA2 computer with SATA3 computer for the mere of SSD speed benefit.
    2
  • slomo4sho
    I understand the desire to pick the best of the best SSD in this test but wouldn't it be more practical to pick the Samsung 840 which is typically 25-30% cheaper than the 840 Pro in this test? If someone is adding a SSD to a dated system, there really isn't any sense in picking the top performing SSD which is bound to be bottlenecked by the 3Gb/s interface.
    9
  • envy14tpe
    Fantastic job once again by the staff at tomshardware. Theoretical vs Real-World. This is the kind of analysis we need!
    9
  • nekromobo
    What kinda queue depths do you get with few virtual machines?

    There could be a test for few linux images + 2 windows images or something..
    This is getting common place, even on laptops. (you can run your company image as VM for example)

    I bet updating few linux VM's will make very high queues :)
    -4
  • ET3D
    Both the SSD's in my HTPC and my desktop are connected at 3Gb/s, because that's what the motherboards supports.

    The conclusion was pretty obvious. In fact I'd say that buying the slowest SSD and connecting it at 1.5Gb/s would still make a significant difference to a PC.
    0
  • ianj14
    I have an Intel X25-M on an old ASUS P5W64 motherboard with SATA 3Gb/s. When I installed it it made one hell of a difference!

    I'm thinking of putting an mSATA Crucial M4 64GiB SSD on an mSATA to IDE adapter to replace the old 80 GiB 2.5 inch HDD in my old laptop. Even though it would only be working at 100MB/s, the seek times would be worth it alone, but the 2.5 inch drive's 22MB/s transfer speed would be outdone by a factor of 4. Still worth it considering the M4 64GiB models are around 50 GBP, + adapter for around 15 GBP.
    1
  • Hupiscratch
    This article was made for me. I'm still using a Asus A8N32SLI Deluxe, and my RAID 0 2 x Seagate Barracuda 9 are showing their age. Upgrading right now!
    1
  • gopher1369
    ET3DBoth the SSD's in my HTPC and my desktop are connected at 3Gb/s, because that's what the motherboards supports.The conclusion was pretty obvious.


    Only to you as you already have an SSD and have real world experience. What about people with a SATA2 motherboard who are thinking about upgrading to their first SSD? This article has helped save them money as they now know that they do not need to upgrade their motherboard.
    2
  • reyshan
    Thank You Tom's for making another great article. I was gonna upgrade my board and Ram so that if I get an SSD it wouldn't be bottlenecked. Now after reading this, I don't have to. Thank You again for the info and taking your time on making an informative article like this. To all the ppl that are bashing that its obvious that 3Gb/s is enough for a SSD like the 840 Pro are not thinking. I am one of the many other ppl that didn't know that because we don't have an SSD and we think upgrading our boards is a first before getting one.
    0
  • jemm
    Congratulations for the excellent article!!! :) It just made my day!!!:)

    I have a SSD (Samsung 830) connected to a SATA 3Gb/s port, even tough my motherboard (P6X58D-E) has 2 x SATA 6Gb/s ports.

    The reason I connected the SSD through the 3Gb/s port, instead of the one 6Gb/s port available is its controllers. The 3Gb/s ports have Intel ICH10R controller, while the 6Gb/s ports have Marvell® PCIe 9128 controller.

    I was told the the Intel ICH10R controller on the 3Gb/s port would be faster than the 6Gb/s ports with Marvell® PCIe 9128 controller.

    I have never tested my SSD on the 6Gb/s port, and I guess I will never will -- or I should?
    2
  • ojas
    Perfmon lists disk queue depths of around 0.5 frequently for my SSDs, and higher for my HDD.

    Apparently, the number of commands actually queued are that reported number x 100, i.e. i'm seeing around 500 commands queued.

    What's up with this? Is this the same queue depth that you guys are talking about? Or do you mean a queue depth of 32 as 3200?
    0