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Samsung SSD 850 Pro review: Top-notch solid-state drive for a premium price

The Samsung SSD 850 Pro is the first solid-state drive on the market that uses the new 3D, vertical NAND flash memory to offer ultra-high endurance, top performance, a great set of features and the all-new 2TB capacity.

Dong Ngo SF Labs Manager, Editor / Reviews
CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.
Dong Ngo
6 min read

Editors' note: The review was updated on July 6, 2015, when the new 2TB version was released.


Samsung SSD 850 Pro

The Good

The Samsung SSD 850 Pro has fast performance, high endurance -- you can write a lot of data to it before it becomes unreliable -- and its 2TB capacity is the highest on the market. The drive comes with a lot of useful features, including encryption, and a great performance-boosting mode called Rapid.

The Bad

The drive is expensive compared with competing solid-state drives. The Samsung Magician software only works with Windows.

The Bottom Line

The Samsung SSD 850 Pro is one of the best standard consumer-grade solid-state drives on the market, but there are cheaper alternatives with similar performance.

There are plenty of reasons to be excited about the Samsung SSD 850 Pro.

It's the first SSD on the market that uses the innovative 3D vertical NAND (V-NAND) flash memory for top performance and ultra-high endurance. It comes with a rarely seen 10-year warranty and, among other features, has a Rapid mode that further boosts its performance. What's more, it's one of the first drives available in the all-new 2TB capacity, along with its sibling the SSD 850 Evo.

Naturally, though, all of that comes at a price. Depending on the capacities, the new Samsung drive is one of the most expensive among standard SSDs, currently costing $98, $152, $255, $489 and $1,000 for 128GB, 256GB, 512GB, 1TB and 2TB respectively. (That's about £63 to £640 and AU$128 to AU$1,310 converted.) Note that the pricing for the newly released 2TB version is the suggested retail price, and its street price will likely be lower.

If you don't mind paying the premium, the Samsung delivers the best performance, highest capacity and longest warranty time currently available on the market. It's especially great for those who regularly need to write a huge amount of data to the internal drive every day. But if you're on stricter budget, the 850 Evo is cheaper, with comparable performance in many tests.

For more options on great internal drives, check out this list of top SSDs on the market.

The 2TB SSD 850 Pro from Samsung Josh Miller/CNET

3D memory cell strings, ultra-high endurance

The Samsung SSD 850 Pro is a standard internal drive that supports the latest SATA 3 (6Gbps) standard and will work in any instance where a regular SATA hard drive is used. Similar to most SSDs, it's 7mm thick. Like most standard drives, it's a square device that's 2.5 inches diagonally, with the standard SATA port on one of its sides. The new drive looks exactly the same as the previous 840 Pro model .

On the inside, however, the new drive is the first that brings 3D vertical NAND flash memory to SSDs, called Samsung second-gen 86-gigabit 40nm MLC V-NAND.

Traditionally, NAND flash memory cells -- the storage units on an SSD -- are placed flat on the surface of the silicon wafer, limiting the number of cells you can cram into a square inch. In the case of the Samsung drive, cells are also stacked up to 32 layers. This allows for packing significantly more memory cells in the same amount of wafer bits, which greatly increases the density. That plus Samsung's customized firmware and the improved MEX controller, allow the drive to also offer great performance and ultra-high endurance.

Endurance is the number of program-erase (P/E) cycles an SSD has before you can't write onto it any more -- read more about SSD endurance here. Samsung says you can write at least 150TB (on the 128GB and 256GB capacities) or 300TB (on the 512GB, 1TB and 2TB capacities) of data to the 850 Pro before it runs out of P/E cycles, almost twice that of the SanDisk Extreme Pro, which has an endurance of 80TB. This means most of us won't use up the drive's endurance in our lifetime.

Samsung SSD 850 Pro specs

Capacities 128GB256GB512GB1TB2TB
Design 2.5-inch 7mm2.5-inch 7mm2.5-inch 7mm2.5-inch 7mm2.5-inch 7mm
Controler Samsung MEX ControllerSamsung MEX ControllerSamsung MEX ControllerSamsung MEX ControllerSamsung MHX controller
Flash memory Samsung 3D V-NAND 2bit MLCSamsung 3D V-NAND 2bit MLCSamsung 3D V-NAND 2bit MLCSamsung 3D V-NAND 2bit MLCSamsung 3D V-NAND 2bit MLC
Included Cache 256MB512MB512MB1GB2GB
Sequential Read 550 MB/s 550 MB/s 550 MB/s 550 MB/s 550 MB/s
Sequential Write 470 MB/s 520 MB/s 520 MB/s 520 MB/s 520 MB/s
Random Read 100K IOPS 100K IOPS 100K IOPS 100K IOPS 100K IOPS
Random Write 90K IOPS 90K IOPS 90K IOPS 90K IOPS90K IOPS
Power consumption (idle) 2mW2mW2mW2mW2mW
Power consumption (read | write) 3.3W | 3.0W3.3W | 3.0W3.3W | 3.0W3.3W | 3.0W3.3W | 3.0W
Endurance (Terabyte written, at least) 150TB150TB300TB300TB300TB
Suggested US retail price $130 $230 $430 $730 $1,000
Warranty 10-year10-year10-year10-year10-year

Helpful software, improved Rapid mode

As with the 840 Pro and 840 Evo , the 850 Pro allows you to manage all of its features via the Samsung Magician software, which is currently only available for Windows.

For example, you can use the software to turn on or off encryption, over-provisioning -- a feature that uses part of an SSD's storage space to enhance the drive's performance -- and Rapid mode. Rapid mode is unique to Samsung SSDs and is the most interesting and appealing feature.

Rapid is an acronym, standing for Real-time Accelerated Processing of I/O Data. It basically means that it uses the available system memory (RAM) on the host computer as an input/output cache to boost the performance. Since most new computers come with a large amount of RAM, Rapid is a welcome feature.

Previously with the 840 Pro and 840 Evo, Rapid used up to 1GB of RAM for cache. Starting with the 850 Pro, Rapid now can use up to 4GB or 25 percent of the host computer's RAM, whichever is larger, as cache. More cache means better performance. In my testing, I found no reason why you shouldn't use Rapid mode.

The Samsung 850 Pro offers a good set of features, including the Rapid mode, via the Samsung Magician software. Dong Ngo/CNET

Premium pricing

Apart from the 2TB, which just came out and has the suggested price of $1,000, the US street prices of the other capacities are at $98, $152, $255, $489 for 128GB, 256GB, 512GB and 1TB respectively. Generally, the drive costs from 47 cents to 59 cents per gigabyte, among the most expensive on the market. The SSD 850 Evo for example, costs just around 33 cents per gigabyte. Note that when buying SSDs, the higher the capacity, the less cost per gigabyte. This means buying larger capacity drives will give always you more for your money.

It's important to note that while the the SSD 850 Pro is faster than the SSD 850 Evo for the most part, in real-world usage, you might not notice at all. The SSD 850 Pro's 10-year warranty, however, is clearly better than the five-year of its sibling.

SSD US street price

WD Black 2 Dual Drive $0.12Transcend SSD370S (512GB) $0.34SanDisk Ultra II (480GB) $0.35Samsung SSD 850 Evo (500GB) $0.36OCZ ARC 100 (240GB) $0.37SanDisk Ultra II (240GB) $0.38Samsung SSD 850 Evo (250GB) $0.38Transcend SSD370S (256GB) $0.39Crucial MX200 (500GB) $0.40Crucial MX200 (250GB) $0.40Samsung SSD 850 Pro (1TB) $0.44Samsung SSD 850 Pro (2TB) $0.45SanDisk Extreme Pro (480GB) $0.46Samsung SSD 850 Pro (512GB) $0.50Plextor M6S (256GB) $0.52OCZ Vector 180 (480GB) $0.53Intel SSD 730 (240GB) $0.55SanDisk Extreme Pro (240GB) $0.57OCZ Vector 180 (240GB) $0.58Samsung SSD 850 Pro (256GB) $0.59Samsung SSD 850 Pro (128GB) $0.77
Note: Measured in cost per gigabyte based on current price on Amazon.com. MSRP used for the 2TB capacity. The lower number indicates better value.

Top performance

The Samsung SSD 850 Pro did very well in testing. I tested the new drive with its 256GB, 512GB, 1TB and the new 2TB capacities and they basically offer the same performance. The drives were tested as a main storage device that host the operating system, since the Rapid mode doesn't work when the drive is used as a secondary drive. The test machine is a midrange computer running a Core i5 processor with 8GB of system memory.

In our sequential data transferring test, the new drive scored a sustained speed of 246MBps when doing both writing and reading at the same time, slightly slower than the 251MBps of the SanDisk Extreme Pro. When Rapid mode is turned on, however, the Samsung registered 287MBps, by far the fastest result.

CNET Labs' SSD data transfer performance

Samsung 850 Pro (Rapid) 287.46Sandisk Extreme Pro 250.98Samsung 850 Pro 246.25Plextor M5 Pro Xtreme 236.18OCZ Vector 150 231.42SanDisk Extreme II 224.27Seagate 600 SSD 192.26
Note: Measured in megabytes per second.

Moving on to the tests with the PC Mark benchmark suite, the new Samsung drive was consistently excellent. The drive also scored the highest compared with other SSDs.

PC Mark 8 overall storage performance

Samsung 850 Pro (Rapid) 5005 368.13Samsung 850 Pro 4979 267.32Sandisk Extreme Pro 4957 244.17Plextor M5 Pro Xtreme 4948 236.18Standard Laptop HDD 2042 6.83
  • Storage Score
  • Storage bandwith (MB/s)
Note: Higher number means better performance.

PC Mark also showed that the Samsung SSD 850 Pro helped improve the application performance slightly compared with the SanDisk Extreme Pro, especially in Rapid mode.

PC Mark 8 storage application performance

Samsung 850 Pro 58.1 133.8 369.8 28.3 9.1 9.2Samsung 850 Pro (Rapid) 58 133.9 355.7 28.2 9.1 9.1Sandisk Extreme Pro 58.4 133.9 361.1 28.3 9.2 9.2Standard Laptop HDD 138.9 366 565.19 51.7 26.6 27.4
  • World of Warcraft
  • Battlefield 3
  • Adobe Photoshop
  • Microsoft Word
  • Microsoft Excel
  • Microsoft PowerPoint
Note: Measured in seconds. Shorter bars means better performance.

In all the Samsung 850 Pro is one of the fastest, if not the fastest SSD on the market. Note that you need to use it in a computer that supports SATA 3 (6Gbps) to be able to fully appreciate its performance.


If money is not an issue, you can't go wrong with the Samsung SSD 850 Pro. The drive has it it all: top performance, plenty of useful features, the highest storage capacity (up to 2TB) and a super long 10-year warranty.

But cost is always an issue and in real-world usage, chances are you won't notice the little extra performance the 850 Pro has over competing drives that are cheaper, such as its sibling SSD 850 Evo that costs some 20 percent less and offers neck-and-neck performance in many tests.

Generally SSDs are all so much faster than regular hard drives that the performance gaps between them are minimal to the user. So while the SSD 850 Pro is a great drive, worthy of the investment for professional users, it does not offer the most for your money.

At the end of the day, if the best deal is what you're after, the 850 Evo is the way to go, but if you want something top-notch without any compromises, the 850 Pro is the drive you want.


Samsung SSD 850 Pro

Score Breakdown

Setup 8Features 9Performance 9Support 10