Average Bench: 60% (506th of 860)

Based on 1,036 user benchmarks.  Models: SAMSUNG SSD PM851 mSATA 256GB, SAMSUNG SSD PM851 mSATA

Average average bench

The Samsung PM851 mSATA 256GB averaged 40.0% 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 23.5MB/s
Avg. Sequential Read Speed 477MB/s

Above average consistency

The range of scores (95th - 5th percentile) for the Samsung PM851 mSATA 256GB is 36.4%. This is a relatively wide range which indicates that the Samsung PM851 mSATA 256GB performs inconsistently under varying real world conditions.


Avg. 4K-64Thread Mixed IO Speed 24.8MB/s
Avg. Sequential Write Speed 176MB/s

Average Bench

(Based on 1,036 samples)
Min Avg Max
372 Read 477 509
37 Write 176 259
73.7 Mixed 241 345
65.2% 298 MB/s
Min Avg Max
12.1 4K Read 23.5 32.9
23 4K Write 53.7 84.6
7.84 4K Mixed 12.4 16.3
80% 29.9 MB/s
Min Avg Max
18.3 DQ Read 188 361
33.5 DQ Write 128 247
8.98 DQ Mixed 24.8 39
54.4% 113 MB/s
User Benchmarks Bench Sequential Random 4k Deep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
181GB free
Firmware: EXT4 Max speed: SATA 3.0 600 MB/s
Read 490
Write 257
Mixed 350
81% 366 MB/s
4K Read 27.5
4K Write 53.2
4K Mixed 14
88% 31.6 MB/s
DQ Read 149
DQ Write 112
DQ Mixed 34.7
52% 98.6 MB/s
198GB free
Firmware: EXT49D0Q Max speed: SATA 3.0 600 MB/s
Read 498
Write 210
Mixed 270
72% 326 MB/s
4K Read 12.6
4K Write 34
4K Mixed 9.21
49% 18.6 MB/s
DQ Read 19.6
DQ Write 29.8
DQ Mixed 10.1
12% 19.8 MB/s
7GB free
Firmware: EXT48D0Q Max speed: SATA 3.0 600 MB/s
Read 392
Write 25.8
Mixed 48.4
33% 155 MB/s
4K Read 32.1
4K Write 49.6
4K Mixed 8.15
85% 29.9 MB/s
DQ Read 34.7
DQ Write 63.4
DQ Mixed 31
29% 43 MB/s
1,036 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 4,120,449 SSDs tested.

Typical PM851 mSATA 256GB Builds (Compare 864 builds) See popular component choices, score breakdowns and rankings.
Gaming 13%
Tree trunk
Desktop 41%
Speed boat
Workstation 23%

System: Dell Latitude E7440


Popular PM851 mSATA 256GB systems:

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Solid State Drive Rankings (Price vs Performance) October 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]


860 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.
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AMD Ryzen 7 1700 $280AMD RX 480 $491Samsung 850 Pro 256GB $126
Intel Core i5-7600K $230Nvidia GTX 1060-6GB $260Samsung 850 Evo 500GB $150
Seagate Barracuda 1TB (2016) $45Corsair Vengeance LPX DDR4 3000 C15 2x8GB $163SanDisk Extreme 64GB $33
Seagate Barracuda 3TB (2016) $75G.SKILL Trident Z DDR4 3200 C14 4x16GB $842SanDisk Extreme 32GB $22
Seagate Barracuda 2TB (2016) $60Corsair Vengeance LPX DDR4 3200 C16 2x8GB $180SanDisk Ultra Fit 32GB $13
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