Average Bench: 60.1% (503rd of 857)

Based on 410 user benchmarks.  Models: SAMSUNG SSD PM851 2.5 7mm 256GB, SAMSUNG SSD PM851 2.5 7m

Above average average bench

The Samsung PM851 2.5 7mm 256GB averaged 39.9% lower than the peak scores attained by the group leaders. This isn't a great result which indicates that there are much faster alternatives on the comparison list.


Avg. 4K Random Read Speed 22.9MB/s
Avg. Sequential Read Speed 477MB/s

Above average consistency

The range of scores (95th - 5th percentile) for the Samsung PM851 2.5 7mm 256GB is 38.4%. This is a relatively wide range which indicates that the Samsung PM851 2.5 7mm 256GB performs inconsistently under varying real world conditions.


Avg. 4K-64Thread Mixed IO Speed 25.1MB/s
Avg. Sequential Write Speed 178MB/s

Average Bench

(Based on 410 samples)
Min Avg Max
355 Read 477 515
36.8 Write 178 260
71.8 Mixed 239 345
65.1% 298 MB/s
Min Avg Max
13.8 4K Read 22.9 29.2
25.6 4K Write 53.6 90.8
7.42 4K Mixed 12.5 16.2
79% 29.6 MB/s
Min Avg Max
19.5 DQ Read 191 361
36.5 DQ Write 136 253
9.27 DQ Mixed 25.1 39.4
56.3% 117 MB/s
User Benchmarks Bench Sequential Random 4k Deep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
164GB free
Firmware: EXT08D0Q Max speed: SATA 3.0 600 MB/s
Read 501
Write 257
Mixed 339
81% 366 MB/s
4K Read 26.3
4K Write 67.4
4K Mixed 15.5
95% 36.4 MB/s
DQ Read 299
DQ Write 250
DQ Mixed 24.7
87% 191 MB/s
188GB free
Firmware: EXT07D0Q Max speed: SATA 3.0 600 MB/s
Read 516
Write 257
Mixed 335
81% 369 MB/s
4K Read 26
4K Write 56.2
4K Mixed 13.1
86% 31.8 MB/s
DQ Read 26.2
DQ Write 60.4
DQ Mixed 13
19% 33.2 MB/s
62GB free
Firmware: EXT08D0Q Max speed: SATA 3.0 600 MB/s
Read 509
Write 99.9
Mixed 167
56% 259 MB/s
4K Read 22.1
4K Write 42.9
4K Mixed 11.6
71% 25.5 MB/s
DQ Read 313
DQ Write 99.1
DQ Mixed 27.4
67% 146 MB/s
410 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 3,541,596 SSDs tested.

Typical PM851 2.5 7mm 256GB Builds (Compare 887 builds) See popular component choices, score breakdowns and rankings.
Gaming 14%
Tree trunk
Desktop 52%
Workstation 34%
Sail boat

System: Dell Latitude E6540

EDIT WITH CUSTOM PC BUILDER Value: 68% - Good Total price: $249

Popular PM851 2.5 7mm 256GB systems:

How Fast Is Your SSD? (Bench your build) Size up your PC in less than a minute.

Welcome to our freeware PC speed test tool. UserBenchmark will test your PC and compare the results to other users with the same components. You can quickly size up your PC, identify hardware problems and explore the best upgrades.

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How it works

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Solid State Drive Rankings (Price vs Performance) August 2017 SSD Rankings.

Welcome to our consumer SSD comparison. We calculate effective speed based on real world performance then adjust by cost per GB to yield a value for money rating. Calculated values don't always tell the whole picture so we check them against thousands of individual user ratings. The customizable table below combines these factors and more to bring you the definitive list of top SSDs. Share your opinion by voting. [SSDrivePro]


857 Drives (Compared) Thousands of user benchmarks compiled into one comparison list.

See how consistently different SSDs perform with varying real world conditions. The charts also illustrate overall performance, popularity and rank.

 Frequently Asked Questions

 Best User Rated

The Best.
Intel Core i7-7700K $300Nvidia GTX 1070 $367Samsung 850 Evo 250GB $90
AMD Ryzen 7 1700 $280AMD RX 480 $390Samsung 850 Pro 256GB $120
Intel Core i5-7600K $212Nvidia GTX 1060-6GB $280Samsung 850 Evo 500GB $165
Seagate Barracuda 1TB (2016) $45G.SKILL Trident Z DDR4 3200 C14 4x16GB $718SanDisk Extreme 64GB $45
Seagate Barracuda 3TB (2016) $77Corsair Vengeance LPX DDR4 3000 C15 2x8GB $140SanDisk Extreme 32GB $22
Seagate Barracuda 7200.14 1TB $57HyperX Fury DDR4 2133 C14 2x8GB $140SanDisk Ultra Fit 32GB $13
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