In this business you hear quite a bit about 'reference designs', but rarely do you hear about the reasons why companies choose to design their own printed circuit boards (PCB). Before SandForce turns thousands of SF-2200 controllers over to companies, they send over a standard circuit board design that allows manufacturers to quickly get products to market.
As with any product, the more time you put into refining it, the better the end result. Reference designs may go through several revisions before they will reach optimal performance. That said, as time passes small issues that can cause problems in rare instances are isolated and solutions are implemented on an ongoing basis to make products better.
Corsair has shared with us their approach in fine tuning their PCB design for the new Force 3 and Force GT products. We've been told this approach increases the clarity of the timing signal and thus should enhance the overall reliability.
Corsair has also made some other changes to the Force 3 and Force GT lineup since we reviewed the 120GB capacity sizes of these models. Corsair now offers the Force GT in 60GB, 90GB, 120GB, 180GB and finally the 240GB size that we are looking at today. The Force 3 is also offered in the same capacity sizes; quite a change compared to the standard 60GB / 120GB / 240GB sizes offered by most manufacturers. The new capacity sizes allow you to get a Force Series SSD at even more price points, an opportunity to maximize your capacity per Dollar.
Specifications, Pricing and Availability
I think everyone has seen these numbers before. The SandForce SF-2281 controller dictates how fast a drive is. Using the right motherboard or controller card, you can hit 555MB/s read and 525MB/s write speeds. At this time your best performance is coming from Intel Z68 and P67 motherboards with native SATA 6Gbps ports.
The SF-2281 controller used in the Force 3 and GT is a fairly unique design. It's been awhile since we talked about the standout features that make the SandForce SF-2281 the best consumer SSD controller on the market today. If you want all of the technical details, check out our SF-2000 Series Client Series article. The short version is SandForce designed their controller to operate without a cache buffer, limit write amplification (write cycles to the actual NAND flash) and perform at the highest data transfer rates.
With so many companies offering SandForce based products on the market today, companies like Corsair have to push the envelope even further to make their products stand out. This has pushed warranties, accessory packages and total cost of ownership to new levels.
We'll start with the current prices available at Newegg at the time of writing. The Corsair Force GT 60GB is now available for 134.99 ($114.99 after a mail-in-rebate), the 90GB is 189.99, the 120GB is 219.99 (189.99 after a mail-in-rebate), the 180GB is 359.99 and the 240GB that we are looking at today is 459.99; the largest capacity size of the current lineup.
Newegg lists 26 240GB SSDs at this time and the Force GT is the lowest priced drive that uses a SandForce SF-2281 controller and synchronous flash. We'll talk about the differences between synchronous flash and asynchronous flash later in the article.
When it comes to add-ons, Corsair includes a three year warranty with the Force GT and a desktop adapter bracket. If you are using your Force GT in a desktop, you'll want a desktop adapter bracket that allows you to install your 2.5" form factor SSD in a 3.5" form factor (standard desktop HDD size) space.
Corsair put together an attractive package for the Force GT. On the front we see the capacity size and some maximum performance numbers.
The back of the package gives some general information about the Force GT and at the bottom we see the full model number of the drive; CSSD-F240GBGT-BK PK1. We'll just stick to calling it a 240GB Force GT.
The inside of the box is divided into two sections, one for the actual SSD and the other for the desktop adapter bracket. Corsair includes screws for mounting your Force GT to the desktop adapter bracket and for installing the total package into your existing computer case.
The Corsair Force GT 240GB
Here we get our first look at the Force GT 240GB. As you can see, the drive is red, a unique color for the latest batch of SandForce based SSDs on the market today.
The Force GT uses an all-aluminum housing, something that is starting to become rare these days after some of the other larger SSD manufacturers have turned to lower cost plastic housings for their products. On the back we see the four mounting points that allow you to install the drive in the desktop adapter bracket and several notebook manufacturers drive sleds.
The side of the drive also has the standard mounting points.
The desktop adapter bracket that's included with the Force GT offsets the drive to the left side. This puts the SATA power and data connectors where they should be and allows you to install the drive in systems that use backplanes.
Here we get our first look at the newly designed PCB used in the new Force 3 and Force GT products. The PCB is quite a bit smaller than the SandForce reference design. This brings all of the components closer together so the timing and data signals don't need to travel as far to get to their destination.
The 240GB capacity size uses sixteen IMFT flash chips, Micron flavored and a single SandForce SF-2281 controller. On this side you can see just how close together the surface mount components are on this new design.
Test System Setup and ATTO Baseline Performance
You can read more about TweakTown's Storage Product Testing Workstation and the procedures followed to test products in this article.
In order to get the most performance out of your Force GT, or for that matter any other SATA III SSD, you need a motherboard with native SATA III built into the chipset. At this time your best performance will come from P67 and Z68 motherboards. I'm currently using a GIGABYTE P67 and am very impressed with its performance.
ATTO Baseline Performance
Version and / or Patch Used: 2.34
ATTO is used by many disk manufacturers to determine the read and write speeds that will be presented to customers.
Using ATTO we found that Corsair's performance claims of 555MB/s read and 525MB/s write speeds were spot on.
Benchmarks - HD Tune Pro
HD Tune Pro
Version and / or Patch Used: 4.00
Developer Homepage: http://www.efdsoftware.com
Product Homepage: http://www.hdtune.com
HD Tune is a Hard Disk utility which has the following functions:
Benchmark: measures the performance
Info: shows detailed information
Health: checks the health status by using SMART
Error Scan: scans the surface for errors
HD Tune Pro gives us accurate read, write and access time results and for the last couple of years has been gaining popularity amongst reviewers. It is now considered a must have application for storage device testing.
We expected to see a very flat line of performance when reading across the drive after Corsair implemented their new PCB design. That isn't what we ended up getting. The line looked more like a data acquisition graph from the suspension with a potentiometer attached on a teenager's car on prom night.
At this point we were worried that the drive had already been brought to a steady state, but a quick look in Crystal Disk Info showed only one previous power cycle.
Even though the graph showed quite a bit of fluctuation, we still achieved an average read speed of 338.3 MB/s.
The write graph in this test showed quite a bit of variation as well. Here we achieved just 315MB/s on average, but the maximum was 364MB/s.
Benchmarks - AIDA64 Random Access Time
AIDA64 Random Access Time
Version and / or Patch Used: 1.60
Developer Homepage: http://www.aida64.com
Product Homepage: http://www.aida64.com
AIDA64 offers several different benchmarks for testing and optimizing your system or network. The Random Access test is one of very few if not only that will measure hard drives random access times in hundredths of milliseconds as oppose to tens of milliseconds.
Drives with only one or two tests displayed in the write test mean that they have failed the test and their Maximum and possibly their Average Scores were very high after the cached fills. This usually happens only with controllers manufactured by JMicron and Toshiba.
The new circuit board did decrease the latency of the new Force GT. Here we see a .1ms difference between the Force GT and the Vertex 3 240GB.
The write latency went up a small amount on average.
Benchmarks - CrystalDiskMark
Version and / or Patch Used: 3.0 Technical Preview
Developer Homepage: http://crystalmark.info
Product Homepage: http://crystalmark.info/software/CrystalDiskMark/index-e.html
Download here: http://crystaldew.info/category/software/crystaldiskmark
CrystalDiskMark is a disk benchmark software that allows us to benchmark 4K and 4K queue depths with accuracy.
* Sequential reads/writes
* Random 4KB/512KB reads/writes
* Text copy
* Change dialog design
* internationalization (i18n)
Note: Crystal Disk Mark 3.0 Technical Preview was used for these tests since it offers the ability to measure native command queuing at 4 and 32.
In CDM we look at 4K and native command queuing performance. In the read test we see good scaling at higher queue depths, but the 4 command performance was a little slower than we wanted to see.
With the commands stacked we see excellent performance coming from the Force GT 240GB. The drive takes off like a rocket ship and doesn't hold back.
Benchmarks - PCMark Vantage Hard Disk Tests
PCMark Vantage - Hard Disk Tests
Version and / or Patch Used: 1.0.0
Developer Homepage: http://www.futuremark.com
Product Homepage: http://www.futuremark.com/benchmarks/pcmark-vantage/
PCMark Vantage is the first objective hardware performance benchmark for PCs running 32 and 64 bit versions of Microsoft Windows Vista. PCMark Vantage is perfectly suited for benchmarking any type of Microsoft Windows Vista PC from multimedia home entertainment systems and laptops to dedicated workstations and high-end gaming rigs. Regardless of whether the benchmarker is an artist or an IT Professional, PCMark Vantage shows the user where their system soars or falls flat, and how to get the most performance possible out of their hardware. PCMark Vantage is easy enough for even the most casual enthusiast to use yet supports in-depth, professional industry grade testing.
FutureMark has developed a good set of hard disk tests for their PCMark Vantage Suite. Windows users can count on Vantage to show them how a drive will perform in normal day to day usage scenarios. For most users these are the tests that matter since many of the old hat ways to measure performance have become ineffective to measure true Windows performance.
HDD1 - Windows Defender
HDD2 - Gaming
HDD3 - Windows Photo Gallery
HDD4 - Vista Startup
HDD5 - Windows Movie Maker
HDD6 - Windows Media Center
HDD7 - Windows Media Player
HDD8 - Application Loading
The synthetic tests allow us to have some insight into why a SSD might perform well in the real world tests, but nothing can tell us how a drive performs in the real world like tests designed to show exactly that. Here we see solid performance that is much better than what the synthetic tests would have led us to believe.
PCMark Vantage - Drives with Data Testing
For a complete breakdown on the Drives with Data Testing please read this article. You will be able to perform this test at home with the files provided in the article - full instructions are included.
SSDs perform differently when used for a period of time and when data is already present on the drive. The purpose of the Drives with Data testing is to show how a drive performs in these 'dirty' states. SSDs also need time to recover, either with TRIM or onboard garbage collection methods.
Drives with Data Testing - 25%, 50%, 75% Full States and Dirty / Empty Test
Files needed for 60 (64GB), 120 (128GB), 240 (256GB)
60GB Fill - 15GB, 30GB, 45GB
120GB Fill - 30GB, 60GB, 90GB
240GB Fill - 60GB, 120GB, 160GB
Empty but Dirty - a test run just after the fill tests and shows if a drive needs time to recover or if performance is instantly restored.
HDD1 - Windows Defender
HDD2 - Gaming
HDD3 - Windows Photo Gallery
HDD4 - Vista Startup
HDD5 - Windows Movie Maker
HDD6 - Windows Media Center
HDD7 - Windows Media Player
HDD8 - Application Loading
It doesn't get any more real world than tests designed to take accuracy to the next level. We feel that a drive shouldn't just be tested out of the box, but also with data on it as it would be used in your system. In looking to build the greatest test of real world, day to day task tests, we stumbled upon the clearest view that answers a frequently asked question; why does my SSD feel slower now than it did when I first installed it?
Most SSDs slow after data is added to the drive. They are still faster than mechanical drives, even when completely full and at their slowest. In order to cut costs and fill even more price points, many manufacturers have chosen to offer products with both synchronous flash like the Corsair Force GT and products with lower cost asynchronous flash, like the Force 3.
The stated performance differences come in the form of incompressible data performance. Synchronous flash is faster than asynchronous flash when dealing with data that is already compressed on SATA III SandForce drives. That is a true statement, but it isn't the full story.
In the chart we see the OCZ Agility 3 with asynchronous flash just before the Corsair Force GT with synchronous flash. The Force GT is much faster than the asynchronous flash equipped drives when data is present. If you are weighing your options between the Force 3 and Force GT, spend your money on the Force GT and walk away with the extra performance offered by synchronous flash when you have data on the drive.
Benchmarks - AS SSD
AS SSD Benchmark
Version and / or Patch Used: 1.2.3577.40358
Developer Homepage: Alex Intelligent Software
Product Homepage: Alex Intelligent Software
AS determines the performance of Solid State Drives (SSD). The tool contains four synthetic as well as three practice tests. The synthetic tests are to determine the sequential and random read and write performance of the SSD. These tests are carried out without the use of the operating system caches.
In all synthetic tests the test file size is 1GB. AS can also determine the access time of the SSD, the access of which the drive is determined to read through the entire capacity of the SSD (Full Stroke). The write access test is only to be met with a 1 GB big test file. At the end of the tests three values for the read and write as well as the overall performance will be issued. In addition to the calculated values which are shown in MB/s, they are also represented in IO per seconds (IOPS).
Note: AS SSD is a great benchmark for many tests, but since Crystal Disk Mark covers a broader range of 4K tests and HD Tune Pro covering sequential speeds, we will only use the Copy Benchmark from AS SSD.
- Copy Benchmark
Err, what the hell is that? Corsair's new design paired with the latest firmware from SandForce has increased file transfer performance by a massive margin! This is an area that SandForce controlled drives used to fall behind in; actually, one of the only areas where SandForce controlled drives fell behind those with Marvell controllers. The Force GT just smashed all of the other drives on our charts in these tests!
Benchmarks - Passmark
Passmark Advanced Multi-User Tests
Version and / or Patch Used: 6.1
Developer Homepage: http://www.passmark.com
Test Homepage: http://www.passmark.com
Many users complain that I/O Meter is too complicated of a benchmark to replicate results so my quest to find an alternative was started. Passmark has added several multi-user tests that measure a hard drives ability to operate in a multi-user environment.
The tests use different settings to mimic basic multi-user operations as they would play out on your server. Variances is read / write percentage as well as random / sequential reads are common in certain applications, Web Servers read nearly 100% of the time while Database Servers write a small amount of data.
The Workstation test is the only single user environment and will be similar to how you use your system at home.
The SandForce SF-2281 controller is nearly identical to the SF-2500 controller found in many enterprise SSDs. With that in mind, it's easier to explain why the controller found in the Force GT is so fast at these enterprise tests.
Changing a products reference design can be a double edge sword. While looking to improve one area of a product, you may inadvertently bring on other issues. I don't think that is the case with the Corsair Force GT, but some of the synthetic performance numbers we achieved may lead to that line of thinking. After looking around the web, we observed that others achieved much better performance in HD Tune Pro than we did with our sample. With that out there, I'm content to just leave HD Tune Pro out of our analysis since the results were in line with a drive that had been stressed prior to arrival at our test facility.
Due to time constraints, we are not able to test long term use or test with several different motherboards. You may have read that a small number of end users have experienced problems using SSDs with SandForce SF-2281 controllers. This issue was turned over to SandForce for a fix, but it appears that Corsair is taking action to improve their Force Series of products on their own. We can't say one way or the other if Corsair has the fix with the new PCB design; we've never had the issue with SF-2281 controlled drives outside of a single sample. Time and of course forum users will tell that story when it's ready to be written.
In the time between finishing this article and it going live on the site, more data arrived about the new redesigned Force GT. We've learned that the improvement to the signal was larger than we once thought. In the chart above we see a typical design on the left and the new Corsair design on the right. The "data eye" in the middle is more pronounced with the new design.
The real question left is how the changes affect your system. The most obvious is going to be systems with longer cables or cables that may be producing a poor signal path to begin with. We've read a handful of reports of MACs having issues with signal quality. In some cases users needed to wrap their notebook SATA cable in aluminum foil to achieve a better signal with SATA 6Gb/s drives. Systems with backplanes are another area where issues can arise from poor signal quality. The biggest benefit may simply be peace of mind knowing that your Corsair Force GT was designed to produce the best possible signal from the start.
Corsair has a nice warranty and accessory package for the Force GT. Goodies include a desktop adapter bracket, active support forum and a three year warranty. All of these are starting to become the norm for SSD products, but it didn't get that way without Corsair's influence.
Our Force GT 240GB sample is now available at Newegg for 459.99. At the time of writing this was the lowest priced SF-2281 / 240GB Synchronous Flash drive available at Newegg. With real SATA III performance (with both compressed and uncompressed data) and this price point, it's impossible to not include the 240GB Force GT as one of the top SSDs on the market today.