While other SSD makers have been aggressively promoting their products in effort to garner market share, Samsung has quietly been putting out their own drives into the marketplace with largely unperceived success by flying under the radar. Part of this is because, per their literature, as of 2006 they are the number one SSD supplier to OEM PC makers. So they are getting their product out there already installed in machines rather than the bulk of their sales being from bare drive consumer upgrades. Intel also sells a lot of drives this way and is perhaps the chief competitor to Samsung for SSDs in OEM machines. Their 830 Series, which we are already a fan of, has also sold well and has been found to be a sound product in the populace. The 840 Series is the newest from Samsung and they are currently offering a "regular" and a Pro model. The standard model uses new 3-bit-per-cell TLC NAND Flash and the Pro series uses good old 2-bit-per-cell MLC NAND Flash.

Samsung 840 Series SSDs: 

Samsung 840 Pro Series SSDs: 

We got our hands on a 250GB version of the non-Pro model to test and see what the fuss is about.

Samsung 840 Front

What's so interesting about the 840 Series is that the non-Pro model we have here contains a type of NAND we haven't tested before - nor has it been made available on any consumer SSD until now. TLC NAND is similar to that of MLC and SLC NAND but each have their own characteristics making them a bit different with each having specific applications for which they are more appropriate. SLC (single level cell) NAND is used almost exclusively in enterprise applications and is known for its endurance and performance characteristics, It's generally too cost prohibitive for consumer applications. Most consumer level drives offer MLC (multi-level cell NAND) which offers a good mix of performance and endurance with a cost more palatable for consumer drives. This is what is found in the 840 Pro model. Finally, TLC (triple level cell) NAND offers the least in terms of endurance and performance and is generally even more affordable than MLC NAND. As the names imply, SLC has one bit per cell, MLC has two, and TLC has three bits per cell.

Samsung 840 Box

Samsung has gone this route for a few different reasons. First, simply because they can. Having the ability to manufacture your own components can be a huge advantage. We know other companies have looked into using TLC NAND before but since there wasn't much demand, the supply wasn't there. Second, is so they could offer a more affordable drive for those that want the quickness of an SSD without needing the absolute fastest drive available. While endurance is rated to be less and a consideration, the time it would take an average user to exhaust the write lifespan of the drive is still measured in years - likely four or more. Currently, we are seeing the 250GB version on the open market for $177.99 although we expect to see this drop as the newness wears off, supply starts to build and Samsung gets a solid supply of the TLC NAND.

Samsung 840 Rear

Samsung 840 Series Features and Specifications:

  • Storage:
  • Features:
  • Power:
  • Operating Systems:
  • Environmental Specs:
  • Weight:
  • Warranty:
  • Product Contents:
  • Samsung 840 Contents

    In our review sample we received the drive with a warranty pamphlet, installation guide, software and manual CD, and a few Samsung SSD stickers. Stickers seem to come with a lot of SSDs anymore. Maybe we should start decorating our test bench with them? Anyway, you can drop an additional Andrew Jackson to get the migration kit not pictured here.

    Samsung 840 Beveled Edge

    The exterior design of the drive hasn't changed much from the 830 Series. It's still a black exterior with an orange square although the square has moved from the corner to the center on one of the long edges. It still has the 7mm thickness, making it compatible with the more compact machine such as ultrabooks and the like. It also shares the nice beveled edges that we saw on the 830 Series which ups the elegance factor a bit. For those who don't really care how it looks on the outside can head to the next page where we'll peek at the inside if we can get the darn thing open.

    Inside The 840 Series

    Opening the drive was a bit of an adventure. Something we feared given the joyous time we had with the 830 Series drive that's currently being held together with tape after we mangled the plastic clips. This time, the screws that stood between us and the innards of the 840 Series drive were of the special tamper resistant pentalobe type; for which we did not have the proper tool. Nor do most people for that matter and of course this is by design so geeks like us don't poke around where we don't belong. However, a little ingenuity, elbow grease, and a stout flat head jeweler screwdriver thankfully did the trick but I now know what to put on my wishlist to Santa. Maybe Samsung will be kind enough to include one next time.
    Samsung 840 250GB Open

    Once open, the PCB is not held in by further encumbrances (thankfully!) and doesn't have anything in the way of thermal pads or shims.

    Samsung 840 250GB PCB

    The backside of the PCB is a bleak landscape of tracers with nary a component in sight.

    Samsung 840 250GB PCB

    The other side is where all the good bits reside as evidenced above.

    Samsung 840 250GB NAND

    First up is the NAND and it's a change of pace for us. You are looking at the first consumer SSD to be constructed with 21nm TLC 400Mbps toggle-mode DDR2 NAND. Most consumer drives use MLC NAND and enterprise drives, more often than not, use SLC NAND. SLC NAND only has one bit per cell, offers the best performance and longest endurance. TLC NAND triples up on the bit per cell, is slower and has the shortest lifespan with MLC NAND falling in between. On this particular drive, we have eight modules at 32GB apiece for 256GB (1GB = 1,000,000,000 bytes) total on board. The Pro model of the 840 Series carries MLC NAND as we mentioned earlier.

    Samsung 840 250GB Cache

    Here we see one of two DDR2 cache chips that total 512MB in capacity (half that for the 120GB drive). This assists with IO activity by buffering data which mitigates the stuttering we saw on some of the early consumer SSD models years ago. Thankfully, those days are gone.

    Samsung 840 250GB Controller

    Here we see the 3-core, eight channel MDX ARM controller (300MHz) that's found on both the regular and Pro 840 Series models and has proven to be a very capable controller. The multiple cores help in multitasking situations like we find with multi-core CPU's, providing more consistent performance with heavy multi-operational loads. According to Samsung, the firmware is based off of the firmware found in the 830 Series and tweaked for various improvements - especially on the Pro version. As always, it supports the necessary functions of wear-leveling, error-correction, TRIM and garbage collection. It's designed for low write amplification which is important when you are working with TLC NAND.

    Test System & Comparison Drives

    Legit Reviews Test System

    All tests were performed on a fresh and up-to-date install of Windows 7 Pro x64 with no other applications running while using AHCI mode set through the BIOS. Synthetic Benchmarks were run with the OS loaded on a 40GB Corsair Force SSD. In between every test, the test drive was secure erased using Samsung's Magician tool as shown below. As such, all results should be indicative of optimal performance. All components were set to their default speeds and are listed below.

    LR Test Bench

    P67 Test Bench

    Intel LGA 1155 Test Platform
    Component Brand/Model Live Pricing


    Core i5 2500k


    ASUS P8P67 Deluxe


    Crucial 2 x 2GB  PC3-10600

    Video Card

    Gigabyte GeForce GT 430

    OS Drive

    Corsair Force 120GB (FW 2.4)

    Power Supply

    Corsair HX1000

    Operating System

    Windows 7 Pro 64-Bit

    Comparison Drives & Other Models We Have Tested

    Since there are so many SSDs out there now with different controllers, we started a reference table of which controllers are used by each drive to help you compare results. Different controllers definitely perform differently and each has various strengths and weaknesses. Like CPU's, even identical drives will have variations in performance and part of that variance may be attributable to the NAND flash used. Since the tests of the drives listed have spanned different test benches and represent different interfaces, we have listed the most recent ones for easy reference.

    CONTROLLER(S) TRIM? Interface
    Corsair Neutron GTX 240GB
    LAMD LM87800 Yes SATA III
    Intel 335 Series 240GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Strontium Hawk 120GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Corsair Neutron 240GB
    LAMD LM87800 Yes SATA III
    ADATA SX900 128GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Crucial V4 256GB
    Phison PS3105-S5 Yes SATA II
    Kingston SSDNow V200 128GB
    Toshiba (JMicron JMF66x) Yes SATA III
    Kingston HyperX 3K 240GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    SanDisk Extreme SATA 240GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Mushkin Chronos 120GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Vertex 4 256GB
    Indilinx Evertest 2 Yes SATA III
    Vertex 4 512GB
    Indilinx Evertest 2 Yes SATA III
    Micron P400e 200GB
    Marvell 88SS9174 Yes SATA III
    Kingston V+200 120GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    RunCore Pro V 120GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Intel 520 Series 240GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Samsung 830 Series 256GB
    S4LJ204X01-Y040 Yes SATA III
    Corsair Force GT 180GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Corsair Force GT 240GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Samsung 830 Series 256GB
    Samsung S4LJ204X01-Y040 Yes SATA III
    OCZ Octane 512GB
    Indilinx Everest
    Yes SATA III
    Corsair Force 3 120GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    Super Talent TeraDrive CT3 64GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    Kingston HyperX 240GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    Corsair Force GT 120GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    Patriot Pyro 120GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    OCZ RevoDrive 3 X2 480GB
    SandForce SF-2200 (SF-2281)x4
    Yes PCI-E
    OWC Mercury EXTREME Pro 6G 240GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    OCZ Vertex 3 Max IOPS 240GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    OCZ Vertex 3 Max IOPS 240GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    OCZ Agility 3 240GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    OCZ Vertex 3 120GB
    SandForce SF-2200 (SF-2281)
    Yes SATA III
    OWC Mercury EXTREME Pro 120GB
    SandForce SF-2200 (SF-2281) Yes SATA III
    Crucial m4/Micron C400 256GB
    Marvell 88SS9174 Yes SATA III
    Corsair Performance 3 Series 128GB
    Marvell 88SS9174
    Yes SATA III
    Intel 510 Series 250GB
    Marvell 88SS9174
    Yes SATA III
    Plextor M2 Series 128GB
    Marvell 88SS9174
    Yes SATA III
    * TRIM is not supported due to the RAID controller.

    CrystalDiskMark 5.0.2 Readout:

    For the Samsung 840 250GB drive, the readout on CrystalDiskInfo 5.0.2 shows that both NCQ and S.M.A.R.T. are enabled, as well as TRIM and the interface is confirmed at SATA III (6Gbps). This is a great free tool to see lots of detailed information about the drive such as the firmware version for which we are running the latest available at the time of testing. Future firmware updates will be available through the Magician software tool.


    Samsung also has their own toolbox application for a variety of tasks such as updating firmware, optimizing the OS, secure erasing, and viewing diagnostic data about the drive. You can also allocate more space for overprovisioning.

    Samsung 840 Magician

    Within the tool, you can get the technical information about the drive, similar to that offered in CrystalDiskMark Info.

    Samsung 840 Magician

    Secure erasing the drive is a breeze with the Magician tool. We'd be happy if all SSD makers offered such a tool and for the ones who do, this and the Intel SSD Toolbox are the most robust.

    ATTO & AS-SSD Benchmarks

    ATTO v2.47

    ATTO is one of the oldest drive benchmarks still being used today and is still very relevant in the SSD world. ATTO measures transfers across a specific volume length. It measures raw transfer rates for both reads and writes and places the data into graphs that can be very easily interpreted. The test was run with the default runs of 0.5KB through 8192KB transfer sizes with the total length being 256MB.

    ATTO - Intel P67 Platform

    Samsung 840 250GB ATTO

    Benchmark Results: Obviously, the 840 Series drive is not going to win any major awards for write speeds with performance being capped around 265MB/s but reads are excellent, hitting the fastest speed in our comparison for the 4MB test.

    Samsung 840 250GB ATTO GRID

    AS-SSD (1.6.4237.30508) Benchmark - Intel P67 Platform

    We have been running the AS-SSD Benchmark app for over some time now and found that it gives a broad result set. The programmer has worked very hard on this software and continues to make updates often so if you use it, show him some love and send him a donation. There are now three tests that are found within the tool and we'll show the results from two of them.

    Samsung 840 250GB AS-SSD

    Benchmark Results: The incompressible nature of the data used in this benchmark had little effect on the outcome of the performance as scores are very much near where we saw on the ATTO benchmark which usually indicates a best case scenario performance outcome. Consistency is good!

    Samsung 840 250GB AS-SSD GRID

    Samsung 840 250GB AS-SSD

    Benchmark Results: Holding true to the statement made above, the level of compression has no discernible effect on the performance as the graph has virtually no slope for either line..

    CrystalDiskMark and PCMark 7

    CrystalDiskMark is a small benchmark utility for drives and enables rapid measurement of sequential and random read/write speeds. Note that CDM only supports Native Command Queuing (NCQ) with a queue depth of 32 (as noted) for the last listed benchmark score. This can skew some results in favor of controllers that also do not support NCQ.

    CrystalDiskMark 3.0.1 x64 - Intel P67 Platform

    Samsung 840 250GB CRYSTALDISKMARK P67

    Benchmark Results: Again we see similar scores that show the 840 Series having very consistent performance which is something of a trend with the Samsung drives.


    PCMark 7 Professional - Intel P67 Platform

    PCMARK 7 Pro

    We are continuing to use the new PCMark 7 software since they have updated it to version 7 which is specifically designed for Windows 7. It measures the performance of the latest PC hardware across a variety of common scenarios. PCMark Vantage 7 supports both system level and component level benchmarking and comprises several different test suites but for the purposes of this review, we employed the secondary storage suite. The nice thing about it is that you can submit your scores online and compare against others.

    Samsung 840 250GB PCMARK VANTAGE

    Benchmark Results: Honestly, I didn't think the 840 Series drive would score as high as it did in this benchmark given the write performance as compared to some of the other drives which illustrates that this benchmark is much more read than write oriented.

    Samsung 840 250GB PCMARK VANTAGE GRID

    Real World & IOPS Tests

    File Copy Times Via Teracopy:

    One of the most common operations performed on a PC is moving/copying files. Using a free application called Teracopy, we copied large numbers of two file types from one folder to another on the same drive. Teracopy allows us to objectively measure the time of transfer and using the same drive prevents other devices from tainting the outcome. The operation requires the drive to perform both sustained read and writes simultaneously. The first set of files is a 5GB collection of JPG's of variable size and compression levels with a few movie (.MOV) files thrown in for good measure since most cameras now take video as well as stills. The second is a collection of MP3 files of various sizes which totals 5GB collectively. These file types were chosen due to their wide use and mixture of file sizes and compression levels.

    Samsung 840 250GB MP3 Copy

    Install Results: Not a big surprise here given that the write speeds are limited for this drive but surely helped along by the triple core controller. Given faster NAND like on the Pro model, these scores would definitely see a large improvement.

    Samsung 840 250GB FILECOPY CHART

    Windows Boot Times Via BootRacer:

    Windows start up/shutdown time is always something people are interested in and we haven't done it in a while because there was little variation with the majority of the SSDs. We recently began using an application called BootRacer to objectively measure the startup times of the drives. All of the instances of Windows were identical and freshly installed with only the video driver installed.

    Samsung 840 250GB Bootracer

    Samsung 840 250GB Boot Chart

    Test Results: The boot times falls just below the median here but by no means slow. As compared to the 10,000RPM VelociRaptor, it flies.

    Samsung Magician Performance Benchmark IOPS

    Samsung's Magician toolbox also has some built in benchmark capabilities so we took the opportunity to run some tests with it. One test sows the IOPS performance of the drive.

    Samsung 840 250GB IOPS

    Test Results: The IOPS performance is nearly dead on what the specifications read for the drive with random reads hitting almost 94,000 and random writes hitting just over 61,000. This is a substantial improvement over the 830 Series on both reads and writes.

    We'll wrap this with a look at the total drive capacity and our final thoughts.

    Final Thoughts & Conclusions

    As it shows in Windows, the Samsung 840 250GB drive has 232GB available to the user. However, using the Magician tool provided by Samsung, the user can adjust the level of overprovisioning allocated to the drive.

    Samsung 840 250GB Properties

    The tool recommends 23.20GB be allocated but the user can specify a different amount as they wish. Theoretically, the greater the amount of overprovisioning, the longer the overall drive life. Given that TLC NAND has a shorter theoretical lifespan than MLC, this can be prudent.

    Samsung 840 Magician

    As illustrated, Windows shows the new available capacity to be 209GB after the execution of the procedure. Overall, it's a very handy tool and adds to the overall value of the drive.

    Samsung 840 250GB Label

    In case you skipped all the way to the end (Et tu, Brute?), you may have missed the fact that this version of the 840 Series drive comes loaded with TLC NAND - the first one of its kind. As such, its performance is more modest than that of some enthusiast level drives in the writes arena but darn good in reads which, if you had to choose, would be where you'd want to see your top speeds. We found it to be a very consistent performer and no slouch when it comes to real world tasks thanks in part to their 300Mhz triple core controller. Reads were consistently in the vicinity of the 530MB/s mark and writes near 240MB/s. It was actually a bit surprising given what we know about TLC NAND that the drive performed as well as it did. The 840 Pro model upgrades to MLC NAND which manifests itself with much higher max writes and, given the performance, obscenely low power consumption numbers of 0.068W active and 0.042W idle according to Samsung. This is a large drop from the 0.24W active and 0.14W idle of the 830 Series. We weren't given the same detail of specification on the non-Pro version but suffice it to say that power usage is higher than that of the Pro model. Take note, those that have mobile PC's with limited battery life! The Pro model also ups the warranty to five years versus the three year warranty on the other model.

    Samsung 840 250GB

    Currently, we find the 250GB version for sale for around $179.99 which works out to be $0.78 per usable GB. For Black Friday, Samsung is bundling Far Cry 3 with the purchase of a 250GB drive. That's a pretty sweet deal! As we stated earlier, as Samsung hits their stride on the TLC NAND, we expect the drives to drop in price. Being able to manufacture 100% of the drive components and software also gives Samsung an advantage in maintaining absolute control of their product quality for which Samsung has a good track record for their SSDs. Ultimately, the inevitable absolute affordability of the drives will put significant pressure on those firms not fully committed to their SSD products and really shake up the market.

    Samsung 840 250GB

    While the performance and value are attractive, we all know how fickle consumers can be and they may just be hesitant to jump on a TLC NAND based drive given the known reduction in endurance as compared to MLC NAND drives. Whether or not users would ever stick with a drive long enough for this to manifest not withstanding. At this point, we may caution users who place a heavier than average workload on their drives as a matter of prudence but for most there shouldn't be a need to worry. The controller should mitigate wear and keep things cherry for years - the number being largely dependent on usage. I personally wouldn't be reluctant to use one in my main PC which gets quite a bit of use. That said, this breed of NAND hasn't seen widespread use either which is always a watch point even though we have full confidence in Samsung's due diligence efforts to thoroughly test it. In the end, we always applaud companies who break the mold and blaze their own path and so offer up our innovation award to Samsung and their 840 Series SSD!

    Legit Bottom Line: Samsung changes things up a bit with the 840 Series as the world's very first consumer TLC NAND based SSD that offers up surprisingly good performance. This is a product that may herald the inevitable attrition of the smaller players in the SSD arena.


    LR Innovation Award