The WD SiliconEdge Blue 64GB, Kingston SSDNow V G2 64GB, OCZ Vertex 2 60GB, and Intel X25-V 40GB offer small capacities but big speed compared to most hard drives. One model ultimately rose to the top, both in real world performance and energy efficiency.
October 31, 2010 by Lawrence Lee
WD SiliconEdge Blue 64GB
|Kingston SSDNow V G2 64GB||Intel X25-V G2 40GB||OCZ Vertex 2 60GB|
|Kingston Technology||Intel||OCZ Technology|
Every component in a modern desktop PC has gradually become many times faster than its analog from a decade ago with the exception of the hard disk drive. Modern models are undoubtedly speedier, but the relative difference is far less compared to the strides made in CPUs, GPUs, etc. Given how fast technology marches, the hard drive is a living electronic fossil. The lack of progress is not surprising as reading and writing data in a HDD is mostly a physical process. It doesn’t much matter how many transistors you can cram onto a HDD’s logic board — the motor still needs to spin the platter, the actuator arms still must move to the correct position so that the heads can perform operations.
Enter the solid state drive, which has been around for a long time, but only recently started to become mainstream due to advancements in Flash memory production. Though still very expensive per byte, the proliferation of the Flash chips found in memory cards, USB keys and mobile devices has brought the price down to the point where a tech-savvy end-user can buy an SSD without feeling like a complete sucker. The capacity of an affordable drive is rather small, but with no moving parts, access time is a hundred times faster, power consumption drops like a stone, and noise vanishes altogether. The resulting package is also smaller and less prone to physical damage.
The anatomy of an SSD is simple, with a 2.5" enclosure housing a small circuit board containing Flash memory chips, a controller, and memory for the controller. Budget drives use NAND Flash with slower MLC (multi-level cell) rather than SLC (single-level cell) chips due to cost and capacity. With many manufacturers using similar Flash chips in these drives, the controller and firmware are usually the biggest difference-makers when it comes to performance. The Flash chips themselves aren’t that fast, but they can make a big impact if large number of chips are paired with a controller with enough channels to access them all at the same time. As a result, some larger SSDs outperform smaller ones from the same product line.
Not only does the controller have to manipulate all the data stored on the drive, it also is responsible for wear-leveling, spreading data evenly across the drive so blocks do not fail prematurely. Flash chips are split into a number of blocks, each with a finite number of writes that can be performed. Once a block is written to too many times, it stops retaining data. There is extra storage available to compensate for this, but eventually the entire drive becomes unusable. If data is written efficiently though, the lifespan of the drive is extended with most having estimated MTBF (mean time before failures) much higher than HDDs.
Three contenders: Intel X25-V G2 40GB, OCZ Vertex 2 60GB, and WD SiliconEdge Blue 64GB. The Kingston SSDNow V 64GB failed to show up for the groups photos.
The Intel X25-M was for a time the consensus choice for a performance MLC SSD. Its introduction two years ago marked Intel’s entry into the SSD arena and virtually assured the mainstream acceptance of SSDs. The X25-V uses the same controller, though it is crippled somewhat because it cannot access as many chips simultaneously. This along with only 40GB of capacity results in its status as a budget SSD. Note that our sample is a 2nd generation drive with 34nm Flash chips.
The Kingston SSDNow V 64GB is a value product, one of the most affordable from a brand name, for its capacity. Unlike earlier Kingston SSDs, which were rebranded Intels, the SSDNow Series V is Kingston’s own make. It uses a JMicron 602 controller with 64KB of cache, possibly the same one used in the WD SiliconEdge Blue. Earlier problematic JMicron controllers used just 16KB of cache.
The OCZ Vertex 2 uses a highly coveted controller from a company called Sandforce that has been making waves in 2010 and is now found in many MLC SSDs. The Sandforce controller uses a compression scheme that reduces the need for having its own separate memory; it has a small cache on the same package as the controller instead. The first Vertex had an Indilinx controller that arguably was the first to make budget SSD performance acceptable.
WD’s SiliconEdge Blue carries an unusually high price, and reportedly, a JMicron controller. JMicron was responsible for a series of controllers that had major problems in earlier generation SSDs, but presumably they’ve gotten their act together for a company like WD to use them. More interesting perhaps is that WD, despite being a giant in the hard drive world was very late to the solid state game; Intel and OCZ have been at it for a few years while the SiliconEdge series is WD’s first SSD offering, introduced some six months ago. The name acknowledges the role of SiliconSystems Inc, an SSD manufacturer acquired by WD in March 2009, in the development of the product.
The drives laid bare.
Both the Intel and OCZ drives came in retail packages with a 3.5" drive adapter included, while the WD and Kingston arrived as bare OEM drives. OCZ went with a shiny silver on black motif while WD and Kingston opted for simple uniform metallic enclosures. The X25-V is the most distinct with its protective rubber bumper running along the outside rim on the top side of the drive.
Specifications: WD SiliconEdge 64GB vs. Kingston SSDNow V 64GB vs.
OCZ Vertex 2 60GB vs. Intel X25-V G2 40GB
SATA 3 GB/s
SATA 3 GB/s
SATA 3 GB/s
SATA 3 GB/s
|Random 4KB Read|
|Random 4KB Write|
2.2 W 3/5 W (read/write)
Our samples were tested according to our standard
hard drive testing methodology. As of mid-2008, we have been conducting most acoustics tests in our own 10~11 dBA anechoic chamber, which results in more accurate, lower SPL readings than before, especially with <20 dBA@1m SPL. Our methodology focuses specifically on noise, and great effort is taken to ensure it is comprehensively measured and described. Performance is covered only lightly, for reasons discussed in detail in the methodology article.
Two forms of hard drive noise are measured:
These two types of noise impact the subjective
perception of hard drive noise differently depending on how and where the drive
Both forms of noise are evaluated objectively and
subjectively. Airborne acoustics are measured in our anechoic chamber using a lab reference
microphone and computer audio measurement system. Measurements are taken at a distance of one meter from the top
of the drive using an A-weighted filter. Vibration noise is rated on a scale
of 1-10 by comparing against our standard reference drives.
Summary of primary HDD testing tools:
Performance Test System:
Performance Test Tools:
A final caveat: As with most reviews, our comments
are relevant to the samples we tested. Your sample may not be identical. There
are always some sample variances, and manufacturers also make changes without
A Windows 7 image loaded with our test suite was cloned to drive and our entire
test suite was run start to finish 3 times with a reboot
in between runs. Hard drives were defragmented after each run as well. The best times were collected for comparison.
Boot and loading times are were SSDs excel with all of the models tested posting significant gains over their hard drive brethren. Even performance hard drives like the newest WD VelociRaptor and Caviar Black fall short, especially in boot time. Among the SSDs, the differences were too small to be considered significant.
In our application tests, the SiliconEdge edge out the Vertex 2 and the Kingston in combined time to completion, notably excelling in the TrueCrypt test. The X25-V had an oddly disastrous showing, putting up an okay result in the ExactFile test but getting absolutely clobbered in TrueCrypt, posting a higher time than any other drive tested, including 5400 RPM laptop hard drives we left off the chart.
When copying files to itself, the WD and OCZ drives rose to the top, with the Kingston besting both with small files but lagging with large ones. The Intel fell behind considerably. The X25-V’s rated sustained write speed is only 35 MB/s, very low even for a budget SSD and both the TrueCrypt and Large File copy tests involve writing big chunks of data.
Timed installs of PowerDVD and 3DMark06 saw the X25-V falling behind some mechanical hard drives once again, this time dragging the SiliconEdge along with it for the ride. The Kingston and Vertex 2 split top installation speed with the two applications.
Switching from a typical 7200rpm 3.5" HDD to a SSD could save you up to 7~8W in active use, and perhaps 5~6W in idle. The thermal savings is not much for the typical desktop system, which will have cooling good enough that such a small power reduction has no impact on noise or heat. Swapping in an SSD has more practical impact in laptops, boosting performance and possibly increasing unterthered run time. The typical 5400 RPM notebook hard drive uses just under 1W when idle and over 2W when seeking. If you could cut that in half, you might gain a 5~10% boost in operating time in an energy efficient laptop.
OCZ Vertex 2 60GB
Kingston SSDNow V
OCZ Vertex 30GB
Intel X25-V G2 40GB
Intel X25-M G1 80GB
WD Scorpio Blue 640GB
Hitachi Travelstar 5K500.B 500GB
WD SiliconEdge Blue 64GB
Kingston SSDNow V G2
NOTE: We added data on some earlier SSDs that came through the lab but were not fully tested.
Excelpt for the Kingston, the SSDs used well under 1W when idle. During seek the SiliconEdge and Kingston consumed 2.5W and nearly 3W, respectively. Assuming a 50/50 split between idle and seek time, the overall energy efficiency of the WD and Kingston SSDs is less than the Scorpio Blue 640GB and Travelstar 5K500.B, the two most frugal notebook drives we’ve tested. The Vertex 2 was fairly efficient, besting all the drives of equal or higher capacity except the Intel X25-M, while the X25-V fell somewhere in the middle.
In regards to laptop battery life, of the four SSDs, only the Vertex 2 provides any significant improvement, though it may still be too small to notice depending on how often the drive is actively used and how much power the rest of the system draws.
In our opinion the biggest advantage of solid state drives is their complete lack of noise. The quietest notebook drives measure 3~4 dB louder than the noise floor in our anechoic chamber (10~11 dBA@1m). SSDs also don’t produce any vibration, so that’s two fewer things we here at SPCR have to worry about. Below is a vibration/noise/power reference table comparing the various SSDs and notebook hard drives we’ve tested.
ALL DRIVES TESTED IN ANECHOIC CHAMBER
(10 = no vibration)
SOLID STATE DRIVES
OCZ Vertex 2 60GB OCZSSD2-2VTXE60G
Kingston SSDNow V 30GB SNV125-S2/30GB
OCZ Vertex 30GB OCZSSD2-1VTX30G
Intel X25-V G2 40GB
Intel X25-M G1 80GB
WD SiliconEdge 64GB
Kingston SSDNow V G2 64GB
n.m. = Not measurable. It’s possible that there could be a tiny bit of electronic noise (typically a high pitched squeal) being emitted by any of these SSDs, either intermittently depending on task, or continuously, but we never heard a thing, even in the anechoic chamber with ear pressed right up against the drives.
HYBRID HARD DRIVES
1.34 W (1.16 W heads unloaded)
NOTEBOOK HARD DRIVES
Hitachi Travelstar 5K320-250 250GB
1.08 W (0.85 W heads unloaded)
Hitachi Travelstar 5K500.B 500GB
0.7 W (0.6 W heads unloaded)
Seagate Momentus 7200.4 500GB ST9500420AS
1.1 W (0.9 W heads unloaded)
Seagate Momentus 5400.6 500GB ST9500325ASG
0.8 W (0.65 W heads unloaded)
WD Scorpio Blue 500GB WD5000BEVT
0.95 W (0.8 W heads unloaded)
WD Scorpio Blue 640GB WD6400BEVT
0.87 W (0.74 W heads unloaded)
All of the reviewed SSDs support TRIM in operating systems that support it, which currently include Windows 7, Windows Server 2008, Solaris and Linux 2.6.33. It is safe to assume that the Mac OS will soon support it as well. TRIM prevents degradation of write performance in an SSD as it is used over time. It is unlikely that you will see any major brand SSDs without TRIM support today.
There are many detailed explanations of the TRIM function, some of which are linked here:
A simplified summary: TRIM deals with the way that operating systems handle data deletion, developed for hard drives which have no way of knowing which files are really in use. When the delete command is issued, the file is simply marked as being not in use, and the block the file occupies is allowed to be overwrtten in a later write (save) operation. Unlike a hard drive, however, an SSD cannot write to an occupied block, so in a conventional OS, the SSD simply writes to empty blocks until they are all full. At this point, every write must be preceded by a delete operation, which naturally takes longer than a single write. Hence, the write slowdown in time as an SSD is used in an OS that does not support TRIM. What TRIM does is to inform the SSD which file can be deleted at the time of deletion, so more of the SSD remains as free space that does not have to be cleared before it is written to. By clearing deleted files immediately, TRIM allows all new files to be saved in a single write operation, so there is no slowdown as the drive is used more and more. TRIM does not improve all save operations, however; the SSD still must delete before writing when you save changes to a document.
While the price of SSDs has dropped dramatically since they first were released, they are still rather expensive propositions. That being said, they have come a long way. Subjectively, it was extremely difficult for us to tell the difference between the SSDs we tested in day-to-day use. We encountered no stuttering with any of them, a problem which plagued cheaper drives from earlier generations, and general performance was snappy. For the most part, the technology has matured to the point where end users need only worry about the overall speed difference and long term reliability between the various drives available.
Based on our real world tests of the three value SSDs examined here, the OCZ Vertex 2 60GB stands out. The Vertex 2 delivered consistently strong results throughout all our performance tests and it managed to accomplish this feat with the best overall energy efficiency. It appears that the much praised Sandforce controller used in the drive is as advertised, offering solid performance for budget MLC SSDs.
The Kingston SSDNow V G2 64GB performed quite well, in some cases better than the Vertex 2. Its biggest drawback is high power consumption, which makes it less suitable for notebooks. It seems a perfectly suitable low-cost high performance OS drive for a desktop.
The Intel X25-V G2 lagged behind the other SSDs in most of our tests, and during a couple of them, its poor write speeds caused a steep nosedive in performance. When large amounts of data need to be written, the drive slows down considerably. It is suitable for basic use though as a 40GB drive isn’t likely going to be used for writing big files often. At US$90, it is also one of the cheapest reputable SSDs you can buy. However we would be remiss not to mention the second generation Kingston SSDNow 64GB as a possible alternative. The extra capacity alone is well worth the extra $20 premium — the better all-around performance is simply a bonus.
The WD SiliconEdge 64GB ran neck and neck with the Vertex 2 until it stumbled in our program installation tests where it fell behind some mechanical hard drives. This hiccup along with its lackluster power consumption, and its extraordinary street price of US$230 makes it a poor buy at the moment. In the past it has gone on sale for ~US$140 which is far more palatable, but it should really be knocked down in price by an additional $20 or so. There is a lot of competition in the US$150 range including a variety of drives using the same Sandforce controller found in the Vertex 2 and the Crucial RealSSD which has been getting excellent reviews.
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SPCR Articles of Related Interest:
WD Caviar Black 2TB & VelociRaptor 600GB
Samsung EcoGreen F4 &
Seagate Barracuda XT 2TB Hard Drives
Seagate Momentus XT: The Best of Both Worlds?
2TB EcoGreen F3 Hard Drive
Digital Green 1.5TB vs. Seagate 7200.12 500GB
500GB notebook drives: Seagate 7200.4 & Hitachi 5K500.B
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