Model: Samsung 950 PRO 512GB M.2 NVMe PCIe Solid State Drive
Manufacturer: Samsung Electronics
Provided By: Samsung America

Samsung Electronics has been a leader in the electronics industry for more than 30 years. Since the introduction of their first television in 1970, this Korean company has grown to become one of the world's leading electronics manufacturers, offering everything from tiny semiconductors to large home appliances. Samsung is no stranger to the storage industry either. Along with an assortment of DVD and Blu-ray Disc drives, the company offers both hard drive and flash based storage solutions for the portable and desktop computer markets.

With solid-state technology advancing at an ever increasing rate, Samsung has begun to look for ways to push performance beyond the limits of the current SATA specification. In addition to technologies like RAPID (Real-time Accelerated Processing of I/O Data), which uses free PC memory as a cache, the company has launched a series of PCIe-based SSDs. The latest addition to this lineup is the 950 PRO. First unveiled at the 2015 Samsung SSD Global Summit in Seoul, the 950 PRO is the first consumer-ready Non-Volatile Memory Express (NVMe) M.2 form factor SSD with V-NAND technology. This cutting-edge drive is powered by Samsung's own 3-core UBX controller and is equipped with up to 512GB of their 32-layer MLC V-NAND flash. Also, thanks to its PCIe Gen 3 four-lane interface, the 950 PRO is able to provide higher bandwidth and lower latency than SATA SSDs.

The 950 PRO is available in 256GB and 512GB capacities. For this review, Samsung sent us the 512GB version of the drive which is capable of delivering up to 2,500 MB/s sequential read and 1,500 MB/s sequential write speeds as well as up to 300,000 random read and 110,000 random write IOPS.

   Samsung 950 PRO 512GB M.2 NVMe PCIe Solid State Drive
General Specifications
Model Number MZ-V5P512BW
Capacity 512GB
Flash Type Samsung 32 layer MLC V-NAND
Controller Samsung UBX
Form Factor M.2 (2280)
Interface PCIe 3.0 x4 (up to 32Gb/s) NVMe 1.1

Sequential Read 2,500 MB/s Max
Sequential Write 1,500 MB/s Max
4K Random Read (QD1) 12,000 IOPS
4K Random Write (QD1) 43,000 IOPS
4K Random Read (QD32) 300,000 IOPS
4K Random Write (QD32) 110,000 IOPS

MTBF 1.5 million hours
Endurance 400TBW

Power Consumption
Active Average 5.7 Watt
Active Maximum 7.0 Watt
Idle 70 mW
Device Sleep 2.5 mW

Operating Temperature 0 ºC to 70 ºC
Humidity 5% to 95%, non-condensing
Shock 1500G , duration 0.5m sec, 3 axis
Vibration 20~2000Hz, 20G

Dimensions and Weight
Dimensions 80.15 x 22.15 x 2.38 mm
Weight 10g

Other Features
AES 256-bit for User Data Encryption
Supports TRIM, SMART and Garbage Collection
DEVSLP power mode
5 year warranty

Needless to say, this is only a taste of what the 950 PRO has to offer. To give you an idea of what to expect, we'll take a closer look at Samsung's new NVMe SSD and then see how well it performs. Does the 950 PRO have what it takes? Can it deliver the performance and features that we've come to expect from Samsung? Keep reading as we find out.


The 950 PRO comes in a small black box. While there aren't a lot of details on the front, the back of the box advertises some of the drive's key features including its V-NAND technology, NVMe interface and 5 year warranty. Inside, you'll find the SSD as well as a small guide with a warranty statement summary and user manual.

Physical Features:

The 950 PRO uses the 2280 form factor for M.2 (NGFF) SSDs. It measures 80.15 x 22.15 x 2.38 mm and tips the scales at a mere 10g. The drive also has an "M key" edge connector which provides PCIe SSDs with up to 4x lanes of bandwidth.

Like the SM951-NVMe and SM953, the 950 PRO uses Samsung's UBX controller. Manufactured using 32nm process technology, this 8 channel controller is equipped with three ARM Cortex-R4 cores running at 500MHz.

For the 512GB version of the 950 PRO, Samsung used their own 32-layer MLC V-NAND flash chips. Looking at the pictures above, you can see that there are two 256GB NAND flash packages on the top of the PCB. The drive also has a single 512MB LPDDR3 DRAM memory chip that is used for caching.

The Samsung Magician software is designed to help users easily manage the health and performance of their Samsung SSD. From the main screen, users can check the health of their drives and view information like the serial number, firmware, capacity and the total bytes written. This screen also shows the version of the NVMe controller driver as well as the speed of the PCIe slot the drive is plugged into.

Magician also gives users the ability to benchmark their drives and optimize the performance by forcing TRIM and Garbage Collection to run. In addition to this, users can download and apply firmware updates using the software.


The 950 PRO does not support OS Optimization. However, using the Over Provisioning feature, users can optimize the performance and lifespan of their drive by resizing the partitions.

The Secure Erase feature provides the option to delete all data on an SSD in a way that it can never be recovered, restoring the drive to its original performance. Magician gives you the option to do this from within Windows. Otherwise, if your SSD is in a frozen state, you can create a bootable USB drive, CD or DVD.

The 950 PRO does not work with Samsung's RAPID (Real-time Accelerated Processing of I/O Data) Mode either. However, considering how fast it is on its own, it's not really needed.

Last, but not least, you have Data Security. From here, users can check and see what security features their drive supports and view its current settings. Looking at the screenshot below you can see that with the current firmware, the 950 PRO only offers support for Class 0. According to Samsung, support for TCG/Opal and Encrypted Drive is coming in a future firmware update.

The test system used in this review was an HP EliteDesk 800 G1. The computer is equipped with an Intel Core i5-2400 CPU, 16GB of DDR3 1333MHz memory, Plextor PX-256M5P 256GB SSD, PNY Quadro K600 1GB PCIe graphics card and Intel 1217-LM gigabit network card. For the operating system, I installed a fresh copy of Windows 8.1 Enterprise.  I should also point out that our test system is not equipped with an M.2 slot so we had to use an M.2 PCIe SSD adapter card.

To test the performance of Samsung's 950 PRO SSD, I ran a series of benchmarks using CrystalDiskMark 3.0.3, HD Tach RW, ATTO Disk Benchmark 2.46, AS SSD, HD Tune Pro 5.50, Anvil's Storage Utilities, Iometer and PCMark 8. For comparison, I've also included test results from the Plextor M6V, Crucial BX200, OCZ Trion 100, Kingston HyperX Savage, Crucial MX200, OCZ Vector 180, Kingston BX100, Samsung 850 EVO M.2, Samsung 850 EVO mSATA, AMD Radeon R7, Silicon Power Slim S80, Samsung SSD 850 EVO, OCZ ARC 100, SanDisk Ultra II, Kingston MX100, SanDisk Extreme Pro, Samsung SSD 850 PRO, Plextor PX-256M6S and Toshiba Q Series Pro.

As I mentioned earlier, the 950 PRO is based on Samsung's UBX controller chip. Looking at the screenshot above, you can see that it performs equally well with both incompressible (0%) and compressible (100%) data.

CrystalDiskMark 3.0.3:

First, I ran a few quick tests using CrystalDiskMark. This benchmark tool measures the performance of a storage device by testing its sequential read and write speeds as well as its random read and write speeds using blocks 512K and 4K in size.

Samsung 950 PRO 512GB
Samsung 850 PRO 256GB

According to Samsung, the 512GB 950 PRO is capable of reading at 2,500 MB/s and writing at 1,500 MB/s. Looking at the screenshot above, you can see that the drive had no problems reaching these speeds in CrystalDiskMark's sequential read and write tests.

HD Tach RW

Next, I used HD Tach to test the 950 PRO's read, write and burst speeds as well as its seek times and CPU usage.

Samsung 950 PRO 512GB

The 950 PRO's performance was hit and miss when tested with HD Tach. While the drive was able to write at 1,562 MB/s, its read speed averaged out at only 1,348.8 MB/s.

ATTO Disk Benchmark 2.46:

I also used ATTO Disk Benchmark to test the 950 PRO's sequential read and write speeds. The tests are run using blocks ranging in size from 0.5KB to 8192KB and the total length set to 256MB.

Samsung 950 PRO 512GB
Samsung 850 PRO 256GB

When tested with ATTO, the 950 PRO's read speeds topped out at about 2,604 MB/s and its write speeds at 1,563 MB/s.


AS SSD is a relatively new benchmark designed specifically for solid state drives. The application contains five synthetic tests used to determine the sequential and random read and write performance of a drive.

Samsung 950 PRO 512GB
Samsung 850 PRO 256GB

AS SSD also includes a copy benchmark. This test copies an ISO (two large files), program (many small files) and game (small and large files), returning the speed and duration of each.

Samsung 950 PRO 512GB
Samsung 850 PRO 256GB

HD Tune Pro 5.50:

Next, I ran a series of tests using HD Tune Pro. This hard disk utility measures a drive's performance by testing its sequential read and write speeds as well as its access time, burst rate and CPU usage. For this review, I'm also going to use it to benchmark the 950 PRO's random read and write speeds, random access times and the number of operations per second.

Samsung 950 PRO 512GB - Read Benchmark
Samsung 850 PRO 256GB - Read Benchmark

Samsung 950 PRO 512GB - Write Benchmark
Samsung 850 PRO 256GB - Write Benchmark

The 950 PRO performed very well when benchmarked with HD Tune. The drive had average read and write speeds of 2179.5 MB/s and 1484.7 MB/s, respectively, and a burst rate of 515.4 MB/s when reading.

Samsung 950 PRO 512GB - Random Access Read
Samsung 850 PRO 256GB - Random Access Read

Samsung 950 PRO 512GB - Random Access Write
Samsung 850 PRO 256GB - Random Access Write

The 950 PRO didn't disappoint when doing random reads and writes. When reading 4KB blocks, the drive reached 41,785 IOPS and had an average speed of 163.223 MB/s. The 950 PRO was even  faster when writing, reaching 55,251 IOPS with an average speed of 215.827 MB/s.

Anvil's Storage Utilities:

Anvil's Storage Utilities is another new benchmark designed with SSDs in mind. The standard storage benchmark measures a drive's performance by testing its transfer speeds, access times and IOPS.


Lastly, I ran a series of tests using Iometer. This tool can be configured to benchmark a number of things. In this case, I used it to measure the 950 PRO's read and write speeds and the number of operations per second. The tests were run using random bytes and a queue depth of 3.

The 950 PRO's performance was very similar to what we saw in our other tests. The drive was able to read at 2443.89 MB/s and write at 1474.81 MB/s.

The 950 PRO also performed very well when doing random reads and writes. In our tests, the drive was able to read at 307.2 MB/s and write at 403.57 MB/s.

According to Samsung, the 512GB 950 PRO is capable of up to 300,000 IOPS when reading and 110,000 IOPS when writing 4K blocks. In our tests, the drive reached 78,643 random read IOPS and 103,315 random write IOPS. Increasing the queue depth had little impact on the 950 PRO's random write performance. However, with the queue depth set to 32, the drive was able to reach 252,844 random read IOPS.

PCMark 8 - Storage Test:

PCMark 8 is a complete benchmark for Windows. It includes five benchmark tests, each designed around a specific scenario. The storage benchmark measures drive performance using real-world traces recorded from Adobe Creative Suite, Microsoft Office and a selection of popular games.

PCMark 8 also includes a consistency test which measures the performance consistency and degradation tendency of a storage system. The test reports the performance level at the start, the degraded steady-state and the recovered state as well as the number of iterations required to reach the degraded state and the recovered state. For this test, we are focusing on the Adobe Photoshop (Heavy) trace and will look at both the bandwidth and latency of the drive

The 950 PRO did quite well throughout PCMark's consistency test. While the average bandwidth dropped below 390 MB/s during the degradation and steady state phases, it was still considerably faster than the OCZ Vector 180 and Kingston HyperX Savage. More importantly, the 950 PRO had no problems bouncing back during the recovery phase.

TRIM Performance:

While SSDs offer many benefits, there are some downsides to using flash memory. One of the biggest issues people run into is performance degradation. Over time, an SSD will run out of fresh blocks and will have to write over data the file system has marked as deleted. This procedure is very complicated and can slow an SSD's write speeds considerably.

To fix this problem, most manufacturers have added TRIM support to their SSDs. The TRIM command allows an operating system, such as Windows 7, to tell an SSD which data blocks are no longer in use. Using this information, the drive pro-actively erases these blocks and adds them to the free block pool.

To test the 950 PRO's TRIM and garbage collection functions, I first put the drive in a "dirty" state. I used Iometer to fill the entire drive and then ran a random write test for 30 minutes. This had little impact on the 950 PRO's read speed. However, its average writing speed dropped to a mere 87.3 MB/s.

Samsung 950 PRO - Dirty

I let the computer sit for about an hour and a half and then reran the test. Looking at the screenshot below, you can see that the 950 PRO's average write speed had increased to a 95.0 MB/s. Needless to say, this was not the result I expected, especially when you consider how well the 850 PRO and EVO did in this test.

Samsung 950 PRO - After TRIM

With this in mind, I went back and reran the test using AS SSD instead of HD Tach. AS SSD isn't as low level as HD Tach nor does it produce a nice looking graph. However, it does let us test a drive's read and write speeds without having to delete the volume. I used Iometer to fill 80% of the drive and then ran a random write test for 30 minutes. Once again, this had very little effect on the drive's read speed. However, its sequential write speed dropped to 393.45 MB/s

Samsung 950 PRO - Dirty

I let the computer sit for about 30 minutes and then reran the test. The 950 PRO wasn't able to reach the factory fresh performance shown in our earlier tests. However, its average write speed climbed up to 1413.21 MB/s.

Samsung 950 PRO - After TRIM

Lastly, I used Samsung's SSD Magician software tpo perform a secure erase on the 950 PRO. With the drive wiped clean, it had average read and write speeds of 2174.87 MB/s and 1446.87 MB/s, respectively.

Samsung 950 PRO - Secure Erase

Dynamic Thermal Throttling:

Normally, cooling isn't something you have to worry about when it comes to SSDs. While they can get a bit warm under heavy workloads, they don't usually generate a lot of heat. This isn't the case with the 950 PRO though.

During testing, I noticed that the performance would often drop off for no apparent reason. An example of this can be seen in the screenshot below.

It wasn't until I touched the 950 PRO that I realized that it was quite hot. At idle, the drive's temperature hovered between 51 ºC and 52 ºC. When pushed hard, these temps jumped up to 76 ºC and, at this point, the performance would drop off.

I reached out to Samsung and they pointed out that this was normal and was caused by the 950 PRO's Dynamic Thermal Throttling (DTT) algorithm. Under high workloads, the temperature of the drive increases rapidly and, to keep it from overheating, the DTT algorithm automatically engages, reducing its performance. Samsung also pointed out that the 950 PRO was designed for client PC usage which includes idle time where the drive would be able to cool off between tasks. However, even basic benchmarks like ATTO and CrystalDiskMark were able to push the drive hard enough where DTT would activate.

To keep DTT from activating, Samsung recommended that I either increase airflow by adding a cooling fan or attach a heatsink to the drive. In this case, I opted to use an 8cm fan that I positioned directly over the 950 PRO. While this solution was a bit extreme, it dropped the drive's idle temps down to 31 ºC with a maximum temp of 50 ºC under heavy workloads. Needless to say, DTT was no longer an issue and I was able to complete the benchmarks without any drops in performance.

Final Thoughts:

If Samsung's 950 PRO SSD is an indication, the future of solid-state storage is PCIe and NVMe. Designed to meet the demands of high-performance consumer and business laptops and PCs, this pint-sized powerhouse combines Samsung's triple-core UBX controller with their 32-layer MLC V-NAND flash. Add in a PCIe Gen.3 four-lane interface with NVMe and you have an SSD capable of delivering performance well beyond that of a single SATA-based drive. In our sequential read and write tests, the 512GB version of the 950 PRO was able to read at speeds as high as 2,604 MB/s and write at speeds in excess of 1,551 MB/s. The drive also took the top spot in our random write tests, producing more than 103,000 IOPS at low queue depths.

Impressive performance isn't the only thing the 950 PRO has to offer. To keep your data safe, the drive offers AES 256-bit full disk encryption with support for TCG Opal and eDrive (IEEE 1667) coming in a future firmware update. The 950 PRO also supports the SATA Device Sleep (DEVSLP) standard which extends the battery life of a device by reducing the drive's power consumption when it's not in use. To top it all off, the 850 PRO is covered by a 5 year warranty.

While more affordable than most other PCIe-based SSDs, the 950 PRO still commands a hefty price tag. The 256GB version of the drive currently sells for about $190 on Amazon with the 512GB version reviewed here going for about $330.


  • PCIe 3.0 x4 interface with NVMe protocol
  • Equipped with V-NAND technology
  • Available in 256GB and 512GB capacities
  • Excellent sequential and random read and write speeds
  • Performs equally well with compressible and incompressible data
  • Small M.2 2280 form factor
  • Large SDRAM cache
  • Supports TRIM and garbage collection
  • AES 256-bit full disk encryption
  • Includes SSD Magician software and Data Migration Tool
  • 5 year warranty


  • Can run hot under heavy workloads
  • Pricey