The EVO Gets Updated

A little over a year ago we got our first look at Samsung's 840 EVO drive, the first drive to prominently feature energy efficient TLC NAND along with really solid performance. It's a drive that was a big hit with consumers because it was priced well and was super power efficient. Plus Samsung's SSD marketing campaign didn't hurt either (remember this gem?). This time around the 850 EVO still features TLC NAND but now it's of the 3D Vertical NAND (V-NAND) variety making it the first to market on the client drive. While other makers haven't even ventured into the TLC NAND market, Samsung is already on their second generation TLC drive. Available capacities are 120GB, 250GB, 500GB and 1TB with MSRP's ranging from $99.99 to $499.99. They sent us over a 120GB and 500GB drive to see what we think. Samsung 850 EVO I could wax on for a few pages about the technical aspects of 3D V-NAND and potentially put you to sleep but I'd rather share this video which does a nice job providing a somewhat technical yet entertaining overview that most will be able to understand. It's actually from the release of the 850 PRO model that came out earlier this year. The 850 EVO also receives a new MGX controller to go along with the new NAND. The outcome of that is performance has been slightly bumped up from the 840 EVO drive, but mainly in the IOPS writes which receives a nice boost. Samsung 840 EVO vs 850 EVO Both the 840 and 850 EVO drives carry the same 540MB/s reads and 520MB/s writes specifications. The warranty has also been increased from 3-years to 5-years.

Samsung 850 EVO 120GB 500GBSamsung 850 EVO Features and Specifications:

Usage Application: Client PCs
Capacity: 120GB, 250GB, 500GB, 1TB (1000GB)
MSRP: 120GB: $99.99 - M27LN120
250GB: $149.99
500GB: $269.99 - M27LN500
1TB: $499.99
Dimensions (LxWxH): 100 x 69.85 x 6.8 (mm)
Interface: SATA 6Gb/s (compatible with SATA 3Gb/s and SATA 1.5Gb/s)
Form Factor: 2.5 inch
Controller: 120/250/500GB: Samsung MGX controller
1TB: Samsung MEX controller
NAND Flash Memory: Samsung 32 layer 3D V-NAND
DRAM Cache Memory: 256MB (120GB) or 512MB(250GB & 500GB) or 1GB (1TB) LP-DDR2
Performance: Sequential Read: Max. 540 MB/s
Sequential Write: Max. 520 MB/s
4KB Random Read (QD1): Max. 10,000 IOPS
4KB Random Write(QD1): Max 40,000 IOPS
4KB Random Read (QD32): Max. 98,000 IOPS (500GB/1TB) 97,000 (250GB) 94,000 (120GB)
4KB Random Write(QD32): Max. 98,000 IOPS (500GB/1TB) 88,000 (120GB/250GB)
Data Security: AES 256-bit Full Disk Encryption (FDE)
TCG/Opal V2.0, Encrypted Drive(lEEE1667)
Weight: Max. 66g(1TB)
Reliability MTBF: 1.5 million hours
TBW: 120/250GB: 75TBW & 500GB/1TB: 150TBW
Power Consumption: Idle: Max. 50mW
Active Read/Write (Average): Max 3.7W(1TB)/Max 4.4W(1TB)
Device Sleep: 2mW(120/250/500GB), 4.mW(1TB)
Supporting features: TRIM (Required OS support), Garbage Collection, S.M.A.R.T
Temperature: Operating: 0°C to 70°C
Non-Operating: -40°C to 85°C
Humidity: 5% to 95%, non-condensing
Vibration: Non-Operating: 20~2000Hz, 20G
Shock: Non-Operating: 1500G, duration 0.5m sec, 3 axis
Warranty: 5 years limited
Samsung 850 EVO 120GB 500GB The exterior design looks very much like its predecessor with the colors reversed. Black is the dominant color and the accent square on the front is grey. The 850 Pro is the same though with an orange accent color.

A Closer Look at the Samsung 850 EVO Drives:

Each drive is disassembled with three screws on the back plate - two of which are hidden under the product sticker. These screws are the pentalobe Torx types which are apparently also very soft and easily stripped to hell. Ask me how I know. Samsung 850 EVO PCB These screws also serves as mounting points for the PCB in each drive. As you can see, both are very small with the 120GB version on the left being much more so and virtually no components on the back side. The 500GB version has two NAND packages on this side. Samsung 850 EVO PCB Flipping them over, we find more NAND, the cache chips and the controllers on each. Samsung 850 EVO NAND The TLC NAND on each drive is Samsung's 32 layer 3D V-NAND with part number K90KGY8S7C. This is the first consumer device on the market equipped with such hardware. Each are 128GB in density so the 120GB only has one and the 500GB drive carried four. This NAND uses about half of the power of the more common Planar 2D NAND and is a key reason the drives consumer very little power comparatively overall. Samsung 850 EVO Cache The cache chips are different capacity depending on the overall drive capacity which is quite common. For the 120GB drive it's 256MB, for the 500GB and 250GB drives it's 512GB, and for the 1TB drive it's 1GB of LP-DDR2 DRAM cache memory. Unless our sample drives are outfitted differently, it's odd that the cache chips on the 120GB and 500GB drives carry the same part number codes etched on the surface. Samsung 850 EVO Controller The Samsung MGX controller, an evolution from the MCX, MDX and MEX controllers, is making its debut on this 850 EVO drive. Well, for all but the 1TB drive at least. That particular one features the MEX controller we've seen previously. What exact changes there are between the MEX and MGX controllers isn't being shared but it's likely the same triple-core ARM design as the MEX controller with subtle differences. We do know that the MGX controller still offers the same great features such as TurboWrite, TRIM and garbage collection support, as well as AES 256-bit encryption as well as TCG/Opal V2.0.

Test System & Comparison Drives

This is our new Z97 test bench and we thank ASUS again for their generosity in providing the Z97-A motherboard for us to use for our testing. All tests were performed on a fresh and up-to-date install of Windows 8.1 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 Crucial MX100 256GB SSD. In between every test, the test drive was secure erased using an instance of Parted Magic. As such, all results should be indicative of optimal performance with the exception being the PCMark 8 consistency test. Power saving modes, sleep and hibernation are all disabled and all components were set to their default/optimized speeds in the BIOS (1304) and are listed below.

Z97 Test Bench

Legit Reviews Z97 Bench

Intel LGA 1150 Test Platform
Component Brand/Model Live Pricing


Intel Pentium G3258


ASUS Z97-A (BIOS v.1204)


Kingston HyperX KHX16C9B1RK28 8GB

OS Drive

Crucial MX100 256GB

Power Supply

Antec Basiq BP550W Plus-EC

Operating System

Windows 8.1 Pro 64-Bit
Comparison Drives And 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.
G.SKILL Phoenix Blade 480GB PCIe SandForce SF-2281 (x4) PCIe
AMD Radeon R7 240GB Indilinx Barefoot 3 M00 SATA III
SanDisk Ultra II 240GB Marvell 88SS9190 SATA III
OCZ ARC 100 240GB Indilinx Barefoot 3 M10 SATA III
SanDisk Extreme PRO Marvell 88SS9187 SATA III
Samsung 850 PRO 1TB MEX S4LN045X01 SATA III
Crucial MX100 256GB & 512GB Marvell 88SS9189 SATA III
ADATA Premier Pro SP920 512GB Marvell 88SS9189 SATA III
Intel 730 Series 480GB PC29AS21CA0 SATA III
Crucial M550 512GB Marvell 88SS9189 SATA III
OCZ Vertex 460 240GB Indilinx Barefoot 3 M10 SATA III
VisionTek PCIe 240GB SSD SandForce SF-2281 (x2) PCIe
WD Black² Dual-Drive 120GB SSD + 1TB HDD JMicron JMF667H SATA III
OCZ Vector 150 240GB Indilinx Barefoot 3 M00 SATA III
Corsair Force LS 240GB Phison PS3108 SATA III
Samsung Evo 500GB MEX S4LN045X01 SATA III
Seagate 600 240GB LAMD LM87800 SATA III
OCZ Vertex 450 256GB Indilinx Barefoot 3 M10 SATA III
Crucial M500 480GB Marvell 88SS9187 SATA III
OCZ Vertex 3.20 240GB SandForce SF-2281 SATA III
Samsung 840 Pro 240GB Samsung MDX SATA III
Sandisk Ultra Plus 256GB Marvell 88SS9175 SATA III
Corsair Neutron GTX 240GB LAMD LM87800 SATA III
Intel 520 Series 240GB SandForce SF-2281 SATA III
OCZ Vector 256GB Indilinx Barefoot 3 M00 SATA III
Kingston SSDNow V300 120GB SandForce SF-2281 SATA III
Samsung 830 Series 256GB Samsung S4LJ204X01-Y040 SATA III

CrystalDiskInfo 6.2.1 Readout:

For the Samsung 850 EVO 120GB and 500GB drives, the readout on CrystalDiskInfo shows that both NCQ and S.M.A.R.T. are enabled, as well as TRIM. This is a great free tool to see lots of detailed information about the drive such as the firmware version for the drive is EMT01B6Q. This is the latest available version for our sample drives but may not be what actually ships with the production drives. CrystalDiskInfo- Samsung 850 EVO 120GB CrystalDiskInfo- Samsung 850 EVO 500GB Samsung also has their own Magician software tool to view drive information and to perform secure erases on the drives and version 4.5 will be released to support the 850 EVOs. It's the same very robust application as previous versions which we've found to be one of the nicer SSD software tools available. Using this software, users can enable RAPID (Real-time Accelerated Processing of I/O Data) mode uses CPU and system memory to cache hot data, serving it out of speedy system DRAM. Let's have a look at the performance with some synthetic benchmarks followed up by some real world tests.

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 Z97 Platform:

ATTO - Samsung 850 EVO 120GB ATTO - Samsung 850 EVO 500GB Benchmark Results: Very similar results between the 120GB and 500GB drives and as strong as any other drive on our comparison. ATTO Grid - Samsung 850 EVO

AS-SSD (1.7.4739.38088) Benchmark - Intel Z97 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. AS-SSD - Samsung 850 EVO 120GB AS-SSD - Samsung 850 EVO 500GB Benchmark Results: Again, the performance is very similar between the two capacities with the biggest disparity coming on the 4K-64 Thrd writes. It's good to see the performance not drop off considerably as some drives do. AS-SSD Grid - Samsung 850 EVO


AS-SSD Compression Chart - Samsung 850 EVO 120GB


AS-SSD Compression Chart - Samsung 850 EVO 500GB Benchmark Results: Obviously, the compressibility of the data has no impact on the performance of the drive with the graph lines having zero slope.

CrystalDiskMark & Anvil IOPS

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 3.0.3 x64 - Intel Z97 Platform

CrystalDiskMark - Samsung 850 EVO 120GB CrystalDiskMark - Samsung 850 EVO 500GB Benchmark Results: Similar results to that of the AS-SSD benchmark with both the 120GB and 500GB drives scoring almost identically and strong results overall. CrystalDiskMark Grid - Samsung 850 EVO There's a relatively new benchmark called Anvil Storage Utilities that is in beta but close to production. It's a very powerful tool that measures performance through a variety of tests which can be customized. Since some of the tests more or less duplicate what we get from other benchmarks we use already, we decided to use the IOPS (Input/Output Operations Per Second) testing on 4kb file sizes at a queue depth of 32. IOPS performance is something SSD makers tout quite a bit but we generally don't do a lot of IOPS testing because frankly a lot of users can't relate to IOPS metrics as well and it tends to be more meaningful to the enterprise/server crowd. Still, it is another performance indicator with relevance and while some drives post good MB/s numbers, their IOPS scores aren't always commensurate which this test will prove out.


IOPS Reads - Samsung 850 EVO 120GB IOPS Writes - Samsung 850 EVO 120GB


IOPS Reads - Samsung 850 EVO 500GB IOPS Writes - Samsung 850 EVO 500GB Benchmark Results: The IOPS performance is roughly equal as well and each do well at high queue depths but at low queue depths, performance drops by about half in writes and about 90% in reads which is huge. IOPS Chart - Samsung 850 EVO

Real World Copy & Boot Tests

File Copy Times Via Teracopy 2.27:

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.


File Copy JPG - Samsung 850 EVO 120GB


File Copy JPG - Samsung 850 EVO 500GB Benchmark Results: The file copy tests definitely show a difference in real-world performance with the MP3 copy taking almost 25 seconds longer on the 120GB drive. File Copy JPG - Samsung 850 EVO

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 start up times of the drives. All of the instances of Windows were identical and freshly installed with only the video driver installed.


Boot Racer - Samsung 850 EVO 120GB


Boot Racer - Samsung 850 EVO 500GB Benchmark Results: The boot times show little difference between the two capacities of the Samsung 850 EVO drives nor any other drives in the chart. Boot Racer Chart - Samsung 850 EVO

PCMark 8 Consistency Test

Something new we are starting to do is run the storage consistency test in the PCMark 8 application from Futuremark. In short, it looks at drive performance degradation as the drive becomes "dirty" and how it rebounds after given time to recover and run background routines like garbage collection and TRIM. This takes nearly a day to run through all of the iterations of test sets. Since most of our benchmarks show the drive performance in a clean state, this is a nice contrast to provide yet another view of performance. PCMark 8's storage benchmark test contains workload traces from Adobe Photoshop, Adobe Illustrator, Adobe InDesign, Adobe After Effects, Microsoft Word, Microsoft Excel, Microsoft Power Point, World of Warcraft and Battlefield 3. The PCMark 8 Consistency test has five phases: Precondition phase
  1. Write the drive sequentially through up to the reported capacity with random data.
  2. Write it through a second time (to take care of over-provisioning).
Degradation phase
  1. Run writes of random size between 8*512 and 2048*512 bytes on random offsets for 10 minutes.
  2. Run performance test (one pass only). The result is stored in secondary results with name prefix degrade_result_X where X is a counter.
  3. Repeat 1 and 2 for 8 times and on each pass increase the duration of random writes by 5 minutes
Steady state phase
  1. Run writes of random size between 8*512 and 2048*512 bytes on random offsets for final duration achieved in degradation phase.
  2. Run performance test (one pass only). The result is stored in secondary results with name prefix steady_result_X where X is a counter.
  3. Repeat 1 and 2 for 5 times.
Recovery phase
  1. Idle for 5 minutes.
  2. Run performance test (one pass only). The result is stored in secondary result with name recovery_result_X where X is a counter.
  3. Repeat 1 and 2 for 5 times.
Clean up
  1. Write the drive sequentially through up to the reported capacity with zero data.
Consistency Chart - Samsung 850 EVO Benchmark Results: The graph is getting a little cluttered but you can see that both capacities of the 850 EVO were heavily impacted by the degreaded and steady state phases with numbers well under 100MB/s but did rebound nicely in the recovery phase of the test.

Final Thoughts & Conclusions

The Samsung 850 EVO 120GB and 500GB drives have 128GB and 512GB (1GB byte = 1,000,000,000 bytes) of NAND on board respectively and yield user addressable capacities of 111GB and 465GB (1Gib = 1,073,741,824 bytes) in Windows as shown in the drive properties. Samsung 850 EVO 120GB Properties Samsung 850 EVO 500GB Properties As with the original 840 EVO drives, pricing is more competitive the larger you get with the 120GB drive being $0.90 per usable GB and the 500GB drive being a very low $0.58 per usable GB.

Samsung 850 EVO MSRP (cost per GB):

If you simply take the advertised capacity and do the math, you can see the progression of the pricing per GB drops as capacity increases. This is contrary to what we see from most drives which tend to get pricier as capacity increases. For comparison, currently the Samsung 850 Pro 128GB drive is selling for $104.99 and the 512GB drive for $319.99. However, these have been on the market closing in on six months now so they prices have come down quite a bit from MSRP as we'd expect to see from the 840 EVO series. The Samsung 850 EVO 500GB SSD is currently $229.99 and comes with FarCry 4. Overall, this pricing puts the 850 EVO series in the middle of the pack with a good number of drives being cheaper but not necessarily offering the same performance. Samsung 850 EVO Box Performance overall is very good but no huge improvements over the 840 EVO and certainly not one that users will be able to  perceive. In terms of published specifications, the 540MB/s reads and 520MB/s writes are unchanged from the 840 EVO but the IOPS performance does get some improvements with 7K more on low queue depth writes and up to 53K more on high queue depth writes for the 120GB and 250GB drives. Write performance is bolstered by TurboWrite which really solidifies writes using an SLC cache to buffer the data. It's supposedly enhanced this time around but what those enhancements are weren't communicated to us. That doesn't factor in the performance improvements offered by RAPID mode which is difficult to measure objectively with benchmarks because it causes a wide range of unpredictable results because it's not designed to support those kinds of operations. As far as we can tell with virtually no inside info from Samsung, the MGX controller appears to be essentially a MEX controller with some minor updates unless you grab the 1TB drive which has the MEX controller. However, there's speculation that it only has two ARM processor cores, not three. For support, the warranty has been bumped up to 5-years which is becoming the new norm and does support AES 256‐bit hardware‐based encryption as well as TCG Opal and IEEE 1667. Samsung 850 EVO Of course, the 3D V-NAND is the big difference for this drive which allows for less NAND packages and therefore requires less juice to run it. Low power consumption is a key feature of both the 840 and 850 EVO drives and the latter supports DEVSLP using a miniscule 2mW for all but the 1TB drive which doubles up to 4mW. We observed the idle power usage on the 120GB drive to be 0.316W and 0.964W on the 500GB drive. The active usage was 2.088W and 2.455W on the 120Gb and 500GB drives respectively. Many drives we see are nearly double that so those with hosts that are battery dependent will find the these drives particularly attractive. The 840 EVO is still a good choice with minimally less performance but no support for DEVSLP. The 850 Pro will be the choice for those more performance oriented, especially as the pricing for the 850 EVO hovers around MSRP a bit after launch.

Legit Bottom Line: Those that want the latest generation Samsung SSD with super low power usage and high performance will definitely want to pick up the 850 EVO drive.