Average Bench: 67.2% (638th of 1011)

Based on 1,134 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 32.8% 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-64Thread Read Speed 318MB/s
Avg. 4K Random Read Speed 23MB/s

Average consistency

The range of scores (95th - 5th percentile) for the Samsung PM851 2.5 7mm 256GB is 42.8%. This is a relatively wide range which indicates that the Samsung PM851 2.5 7mm 256GB performs inconsistently under varying real world conditions.


Avg. Sequential Mixed IO Speed 154MB/s
Avg. Sustained Write Speed 172MB/s

Average Bench

(Based on 1,134 samples)
Min Avg Max
321 Read 427 497
47.5 Write 185 262
78.6 Mixed 154 199
39.5 SusWrite 172 255
51.7% 234 MB/s
Min Avg Max
12.5 4K Read 23 30.9
25.7 4K Write 58 95.9
14.3 4K Mixed 23 29.8
94.9% 34.6 MB/s
Min Avg Max
57.1 DQ Read 318 373
47.6 DQ Write 169 256
29.2 DQ Mixed 70.9 84
98.8% 186 MB/s
User Benchmarks Bench Sequential Random 4k Deep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
119GB free (System drive)
Firmware: 8D0Q
SusWrite @10s intervals: 211 201 37 170 147 157 MB/s
Read 464
Write 226
Mixed 184
SusWrite 154
57% 257 MB/s
4K Read 25.4
4K Write 93.3
4K Mixed 29.8
126% 49.5 MB/s
DQ Read 366
DQ Write 211
DQ Mixed 78.1
115% 218 MB/s
17GB free (System drive)
Firmware: EXT08D0Q
SusWrite @10s intervals: 161 66 74 58 59 142 MB/s
Read 317
Write 67.2
Mixed 97.5
SusWrite 93.2
31% 144 MB/s
4K Read 20.9
4K Write 41.9
4K Mixed 24.7
86% 29.2 MB/s
DQ Read 363
DQ Write 71.8
DQ Mixed 62.9
86% 166 MB/s
1,134 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 19,368,266 SSDs tested.

Typical PM851 2.5 7mm 256GB Builds (Compare 4,161 builds) See popular component choices, score breakdowns and rankings.
Gaming 13%
Tree trunk
Desktop 51%
Workstation 31%
Sail boat

System: Dell Latitude E6540

EDIT WITH CUSTOM PC BUILDER Value: 50% - Above average Total price: $475

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.

UserBenchmark of the month

How it works

  • - Download and run UserBenchMark.
  • - CPU tests include: integer, floating and string.
  • - GPU tests include: six 3D game simulations.
  • - Drive tests include: read, write, sustained write and mixed IO.
  • - RAM tests include: single/multi core bandwidth and latency.
  • - Reports are generated and presented on userbenchmark.com.
  • - Identify the strongest components in your PC.
  • - See speed test results from other users.
  • - Compare your components to the current market leaders.
  • - Explore your best upgrade options with a virtual PC build.
  • - Compare your in-game FPS to other users with your hardware.
  • - Share your opinion by voting.
Solid State Drive Rankings (Price vs Performance) November 2019 SSD Rankings.

Welcome to our 2.5" and M.2 SSD comparison. We calculate effective speed for both SATA and NVMe drives based on real world performance then adjust by current prices per GB to yield a value for money rating. Our calculated values are checked against thousands of individual user ratings. The customizable table below combines these factors to bring you the definitive list of top SSDs. [SSDrivePro]


Group Test Results

  • Best user rated - User sentiment trumps benchmarks for this comparison.
  • Best value for money - Value for money is based on real world performance.
  • Fastest real world speed - Real World Speed measures performance for typical consumers.


1011 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 i5-9400F $140Nvidia GTX 1660S (Super) $230Crucial MX500 250GB $45
Intel Core i5-9600K $195AMD RX 590 $185Samsung 850 Evo 120GB $150
Intel Core i7-9700K $340Nvidia RTX 2060 $325Samsung 860 Evo 250GB $51
Seagate Barracuda 1TB (2016) $39Corsair Vengeance LPX DDR4 3000 C15 2x8GB $71SanDisk Extreme 64GB $72
WD Blue 1TB (2012) $40G.SKILL Trident Z DDR4 3200 C14 4x16GB $609SanDisk Extreme 32GB $46
Seagate Barracuda 3TB (2016) $85Corsair Vengeance LPX DDR4 3200 C16 2x8GB $68SanDisk Extreme 16GB $24
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