Today's fastest SSDs already bounce off the SATA 6Gb/s interface's throughput ceiling. Does a 3 Gb/s link kill the performance of those drives? We run a number of synthetic and real-world tests to assess the damage when you upgrade an older platform.
There are many ways to tune up a PC. But usually, the only way to extract big performance gains is to start replacing hardware. Overclocking remains popular. However, it was arguably a more effective way of milking gains from CPUs, GPUs, and memory back in the day. Take a Celeron 300A, get it to 450 MHz, and you have a 50%-higher frequency. It'd take a 5.25 GHz overclock to get the same boost from a Core i7-3770K. And even then, there's no guarantee that the desktop applications you run would scale as well.
We've burned enough components to know that overclocking has its risks, too (that's why Thomas sticks to processor voltages of 1.35 V or less in his 7-series chipset-based motherboard round-ups). Tweaking around with reference clock rates, multipliers, voltages, and latencies can hammer your system's stability in a hurry.
Once you're happy with your processor and motherboard, swapping in a new graphics card, doubling your RAM on the cheap, and adding an SSD are all great ways to balance performance and keep your machine running optimally. Today, we're focusing on solid-state storage, which dips down under $1/GB in many cases, making it more economically feasible now than ever before. We've said it before and we'll say it again: if you don't have an SSD yet, get one. It'll alter your perception of responsiveness.
Modern SSDs slam right up against the SATA 6Gb/s interface's throughput ceiling, while mechanical hard disks aren't much faster than they were five years ago. Perhaps more important than the 550 MB/s many solid-state drives achieve in sequential data transfers, however, is their ability to handle random I/O deftly in the real world. An SSD can usually field orders of magnitude more requests per second than conventional media (tens of thousands versus a couple hundred).
We can rip off speeds and feeds all day. The point is that we've run the numbers; we know an SSD is a worthwhile upgrade for anyone with a hard drive in their PC still. Windows boots faster, apps launch quicker, and files end up where you need them sooner.
But Is An Old SATA 3Gb/s Port Enough For A Modern SATA 6Gb/s SSD?
We ask this question every time we run out of ports on our mainstream Intel-based platforms, which only offer two 6 Gb/s SATA ports (Ed.: In fact, I'm currently capturing video on a four-drive array of Crucial m4s connected to 3 Gb/s ports). And what if you have an older machine limited to the previous-gen standard? Is the upgrade still worthwhile? Given that we've already seen the fastest SSDs capped by 6 Gb/s SATA, it's safe to bet that a 3 Gb/s port is going to limit performance. But how much? Does it make a palpable difference, or is it only something you'd see in benchmark results? Should you upgrade your storage controller, too?
In search of answers, we took Samsung's 840 Pro, hooked it up to a 6 Gb/s port, and then attached it to a previous-gen interface. While the Samsung drive is one of the fastest out there, consider these results representative of most high-end SSDs. Note also that we left out SATA 1.5Gb/s. It would have been nice to include for the sake of a third data point; however, that takes us all the way back to 2005 or thereabouts. If your PC is eight years old, it's time for a new one.
- Are SSDs Still The Most Noticeable PC Upgrade?
- Hardware And Test Setup
- Real-World Benchmark System And Software
- Results: Sequential Read And Write Performance
- Results: Access Time
- Results: 4 KB Random Read And Write Performance
- Results: 512 KB Random Read And Write Performance
- Results: I/O Benchmark Profiles
- Results: PCMark 7 And Trace
- Results: PCMark Vantage
- Results: AS-SSD Copy Benchmark
- Results: Overall Performance
- Real-World Benchmarks: Booting Up And Shutting Down Windows 8
- Real-World Benchmarks: Booting Up Windows 8 And Adobe Photoshop
- Real-World Benchmarks: Five Applications
- Even With SATA 3Gb/s, An SSD Makes Sense

Thanks toms, Samsung will get a few hundred out of me next pay day.
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.
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!
still the price is the issue...
hope the price will continue to decline, so it became affordable for (most of) everyone....
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.
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 ?
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.
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
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.
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.
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.
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?
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?