Every year Samsung releases a brand new SSD product and this year is no exception. For 2015, Samsung introduces the world’s first (another one) NVMe PCIe SSD the Samsung 950 PRO [official 950 Pro page].

Ubergizmo-editors-choice-2015-001The 950 PRO is basically assembled with the best components and features that Samsung SSD has to offer to date. The board and the controller are from the OEM SM951-NVMe while the memory are from the gen2 3D V-NAND fitted in the 850 PRO series. Also counted as an upgrade are the 512MB of LPDDR3 vs the LPDDR2 cache.


Performance wise, the 512GB version is the fastest between the two, clocking at 2.5GB/s sequential read and 1.5GB/s sequential write compared to the 256GB model raching 2.2GB/s in sequential read and 900MB/s in sequential write.

Those are amazing numbers when considering that SATA 3 SSD drives maxed out at 550MB/s!


Samsung SSD 950 PRO

Usage Application Client PCs
Capacity 256GB, 512GB
Dimensions (LxWxH) Max 80.15 x Max 22.15 x Max.2.38 (mm)
Interface PCIe 3.0 x4 (up to 32Gb/s) NVMe 1.1
Form Factor M.2(2280)
Controller Samsung UBX controller
NAND Flash Memory Samsung 32 layer 3D V-NAND
DRAM Cache Memory 512MB LPDDR3
Performance* 256GB 512GB
Sequential Read: Up to 2,200 MB/s Up to 2,500 MB/s
Sequential Write: Up to 900 MB/s Up to 1,500 MB/s
4KB Random Read (QD1): Up to 11K IOPS Up to 12K IOPS
4KB Random Write (QD1): Up to 43K IOPS Up to 43K IOPS
4KB Random Read (QD32): Up to 270K IOPS Up to 300K IOPS
4KB Random Write (QD32): Up to 85K IOPS Up to 110K IOPS
Weight Max. 10g (512GB)
Power Consumption Active average/maximum: 5.1W/6.4W (256GB), 5.7W/7.0W (512GB)
Idle: 70mW
DEVSLP(L1.2 mode): 2.5mW

Samsung SSD 950 PRO Features

TRIM Support Yes (Requires OS Support)
Garbage Collection Yes
S.M.A.R.T Yes
Data Security AES 256-bit Full Disk Encryption (FDE)
TCG Opal Family Spec and eDrive (IEEE1667) to be supported by FW update
Reliability MTBF: 1.5 million hours
TBW 256GB : 200TB, 512GB : 400TB
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


Description Capacity (GB) Model $/GB
Samsung SSD 950 PRO 250GB M.2 PCIe NVMe 256 GB $199.99 $0.78
512GB $349.99 $0.68

Internals and Features

The device is single-sided, meaning all components are stacked on one side of the PCB. Under the sticker are two 32 layer 128Gb memory V-NAND package, one 512MB LPDDR2 RAM cache and the UBX controller ARM Cortex-R4 3-core 8 channel at 500 Mhz.

The biggest drawback with a high-speed clock controller is cooling. Compound with the fact that the M.2 slot on most of the motherboards are located between two PCIe slots where the air flow may not reach. The heat issue is addressed with the “Dynamic Thermal Guard” which basically reduce the clock speed to prevent data loss and/or hardware damage. I wonder if it is worth to use some memory heatsinks and thermal tape on all 3 chips (2 V-NAND and the controller) to help with cooling.


Introduced with the 850 PRO, the 3D V-NAND revolutionized the SSD industry. I already detailed the specific in the 850 PRO review, but here are the essentials. Up to the V-NAND, the race was about shrinking the die, cramming more and more cells in the same space. On one hand, costs are reduced and prices drop. On the other hand, as the cells are getting closer and closer, error rates increased and writes required higher voltage.

Instead of shrinking, V-NAND stacks vertical layers. By going vertical, there are now more real estates for the cells in size and in between. Which translates into more room for voltage state changes, less interference and lower programming voltage. The benefits are, fewer retries due to interferences, lower power consumption, increase NAND endurance and overall I/O performance


Although Windows 8.1 and 10 provide native driver for NVMe drives, most of the Magician feature will require Samsung custom drivers. At the time of the review, an executable beta version of the drivers was provided.

Software Package

“Samsung Data Migration” is a convenient disk cloning software by Clonix. The utility will always detect the OS drive as the source, which is a good failsafe. It only works if at least one SSD is a Samsung. At this time, it is Windows only. The latest version 2.7 puts a new restriction, it only recognized Samsung SSD as the target drive, meaning I can not choose a non-Samsung SSD drive as a target.

The previous version would only care if at least one drive was a Samsung product. Although the Samsung Data Migration will get the job done, truth to be told, I like the Intel Data Migration better. It has a couple more features  such as creating a bootable media rescue disk and a drive cleaner tool. Although “secure erased” would be as efficient.


Missing from the Magician 4.8:

  • “Performance Optimization”, “OS optimization” and “Rapid Mode” would probably become available in the next Magician update.
  • AES 256-bit FDE with eDrive and TCG Opal are not supported until a new firmware update within the release date.

Testing Protocol

I went through most of the popular benchmark tools, AS SSD, CrystalDiskMark, ATTO, IoMeter, Anvil’s Storage Utility v1.1.0 and PCMark Vantage. But I also used performance monitoring tools such as DiskMon and hIOmon, primarily to validate the tests.

Instead of posting chart after chart, I believe, as a consumer, what is important is how the product fits the needs and not chasing after uber high numbers which are only attainable during benchmarking. For this review, I narrowed it down to Anvil’s Storage Utility, PC Mark Vantage Licensed Pro version, CrystalMark and PCMark8.

Drive conditioning: The SSDs were prepped with Windows 7 (from an image), filled with about 120GB of data total and benchmarks were run from the tested unit acting as the OS drive.

Steady state: This state occurred over time when the drive went through enough write cycles, or to be more specific program/erase (P/E) cycles, that write performances were consistent or stable. It may take a few weeks before the SSD reaches it, depending on the computing usage, but it can be accelerated using IoMeter.

In summary, Steady State is: Written Data = User capacity x 2, at least.

Benchmark Workstation Main Components
CPU INTELr CORE I3-6300 PROCESSOR BX80662I36300 @3.80GHz
Motherboard MSI Z170A GAMING M7 LGA 1151
OS Windows 10 Pro 64bits
OS Hard Drive The reviewed SSD unit
mSATA Adapter N/A
M.2 Adapter N/A

What numbers are relevant in a real world usage?

Keep in mind that unlike synthetic benchmarks which perform only one specific operation at the time for a predetermined duration, seq read, then seq write then random read, and so on and so forth, real world usage paints a different picture.

All four access types can occur at any time, and different transfer rates and different (I/O access) percentages. For instance, a storage subsystem on a streaming server would mostly see high seq read I/O, large block reads, with very little to none write.

Looking at a database server without blob data type, we would probably see 75% random read, 20% random write and 5% random and seq write. I could either guesstimate the different ratios or figure a method to define a more accurate I/O usage baseline.

I/O Baseline

While it is entertaining to run a bunch of benchmarking tools, expecting huge numbers, the purpose of testing the units is to get a good look at how they perform under realistic desktop usage pattern. That is why I picked PCMark Vantage suite as my usage pattern. By capturing and analyzing I/O during the PCVM run, disk operations are breakdown to percentage read vs. write, random vs. sequential, queue depth and average file transfer size.

With that information, benchmarking makes more sense since all the numbers do not carry the same importance, thus some results are more valuable than others.

In summary, I/O pattern defines what I need from the device vs. what can the device do overall.

The I/O baseline process was explained in the Intel 525 mSATA review.


From the numbers, I rated the I/O usage by activity as follow: Random Read > Random Write > Seq Read > Seq Write and average file size is 128K.

To cover Queue Depth, I used hIOmon during the PC Vantage full run. There is a trial version for a week, which is enough time to build the baseline. Based on the chart below, it is obvious that a benchmark score from a QD 16 (or more) does not carry the same weight as a score from a QD 1.


About 95%+ of the reads/writes I/O are at or under Queue Depth 4. Although the bulk of it is at Queue Depth 2 or under.


Unfortunately, I did not have the opportunity to review any other NVMe PCIe SSD prior to the 950 PRO. It is also unfair to compare SATA 3 SSD to high-performance NVMe PCIe SSD unit, but the reality is that many of you will upgrade from SATA 3.

Look at this from a potential upgrade perspective: would a 950 PRO NVMe PCIe SSD improve my system performance?



High QD and sequential I/O take the most advantage of the PCIe x4 bandwidth! If you are running heavy I/O applications, 950 PRO is a must!

PCMark Vantage showed a significant improvement with the “HDD” and the “Productivity” test.

950 PRO on an “older” motherboard.

Out of curiosity, I managed to perform a CrystalDiskMark test on the 950 PRO with a  Z77 motherboard and Windows 7 PRO.

To get the 950 PRO (with a M.2 adapter) recognized in Windows 7 on a Z77 motherboard was a bit tricky. The system already had a bootable Windows 7 PRO drive. The good news was the 950 PRO was detected in the BIOS. Once the O.S. loaded, the 950 drive was not detected. The hardware was showing with an exclamation point in device manager.

I installed the Samsung NVMe driver, only then, the drive was detected. Next, the drive was cloned with “Data Migration”. That allowed the 950 PRO to boot up on a Z77 motherboard.


While there is a performance improvement using an M.2 apdater and the 950PRO the ratio perf/$ may not be favorable.


Will it replace the Samsung SSD 850 series? I think not. The SATA 3, especially the 850 EVO version is still “the best bang for the buck”.

Should you get it? It comes down to your computing usage and your workstation setup.

For a basic home computing usage, which revolves around internet browsing, casual gaming and media streaming, there is really no benefit to make the jump.

"THE MOST COMPETITIVE NVME PCIE SSD "Assuming I am considering the 950 PRO, because I am looking into get a new PC setup, hopefully based on Skylake and the Z170 chipset. In that scenario it will definitely make sense to go with the 950 PRO to take advantage of the native M.2 NVMe motherboard support.

Assuming that you are a power user working with heavy imaging, sounds, 3D rendering applications and/or virtualization then the 950 PRO would be very appealing because of its high sequential I/O performance.

Gaming experience could be improved if the maps are big enough to make it worthwhile. This is the case for many top games these days.

Taking into account that street price tends to be lower than the MSRP, from a price/size/performance/warranty perspective, the 950 PRO is the most competitive NVMe PCIe SSD  on the market at this time.

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