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.
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Far Out! I didnt realise there was such a big difference between my Raptor, and a Samsung's 840,Reply
Thanks toms, Samsung will get a few hundred out of me next pay day. :P
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.Reply
This... was a kind of stupid test. Of COURSE an SSD is a good thing even on a SATA II connection.Reply
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.
Even With SATA 3Gb/s, An SSD Makes SenseI 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!
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.Reply
IMO It well worth it, if u had the budget... (even it in sata2 mode)Reply
still the price is the issue...
hope the price will continue to decline, so it became affordable for (most of) everyone....
Yes it isReply
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.Reply
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. 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.Reply
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 ?
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.Reply
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.