Average Bench: 128% (167th of 1058)

Based on 1,237 user benchmarks.  Model: PM991 NVMe Samsung 512GB

Outstanding average bench

The Pm991 NVMe Samsung 512GB averaged 28.1% higher than the peak scores attained by the group leaders. This is an excellent result which ranks the Pm991 NVMe Samsung 512GB near the top of the comparison list.


Avg. 4K-64Thread Mixed IO Speed 396MB/s
Avg. 4K-64Thread Read Speed 585MB/s

Terrible consistency

The range of scores (95th - 5th percentile) for the Pm991 NVMe Samsung 512GB is 118%. This is a particularly wide range which indicates that the Pm991 NVMe Samsung 512GB performs inconsistently under varying real world conditions.


Avg. Sustained Write Speed 332MB/s
Avg. Sequential Mixed IO Speed 577MB/s

Average Bench

(Based on 1,237 samples)
Min Avg Max
593 Read 989 1,413
125 Write 592 1,317
175 Mixed 577 1,221
101 SusWrite 332 650
138% 622 MB/s
Min Avg Max
19.8 4K Read 34.2 49.2
47.8 4K Write 88.4 134
25.2 4K Mixed 44.1 69.2
155% 55.6 MB/s
Min Avg Max
315 DQ Read 585 904
91.3 DQ Write 327 879
134 DQ Mixed 396 743
311% 436 MB/s
User Benchmarks Bench Sequential Random 4k Deep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
403GB free
Firmware: 25304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 1356 1314 1301 580 350 353 MB/s
Read 1,301
Write 975
Mixed 1,137
SusWrite 876
241% 1,072 MB/s
4K Read 48.1
4K Write 137
4K Mixed 69.3
234% 84.9 MB/s
DQ Read 895
DQ Write 893
DQ Mixed 710
584% 833 MB/s
262GB free (System drive)
Firmware: 25309039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 655 1222 574 306 308 321 MB/s
Read 1,348
Write 1,361
Mixed 1,118
SusWrite 564
246% 1,098 MB/s
4K Read 39.3
4K Write 88.8
4K Mixed 42.1
160% 56.7 MB/s
DQ Read 682
DQ Write 863
DQ Mixed 737
566% 761 MB/s
1,237 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 42,797,532 SSDs tested.

Typical NVMe Samsung 512GB Builds (Compare 592 builds) See popular component choices, score breakdowns and rankings.
Gaming 12%
Tree trunk
Desktop 68%
Battle cruiser
Workstation 11%
Tree trunk

System: Dell Latitude 5510


Popular NVMe Samsung 512GB 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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  • - 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.
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Solid State Drive Rankings (Price vs Performance) May 2021 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.


1058 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 i5-11400F $196Nvidia RTX 3060-Ti $400Crucial MX500 250GB $50
Intel Core i5-11600K $255Nvidia RTX 3070 $500Samsung 850 Evo 120GB $78
Intel Core i5-10600K $217Nvidia RTX 3080 $700Samsung 860 Evo 250GB $40
Seagate Barracuda 1TB (2016) $35Corsair Vengeance LPX DDR4 3200 C16 2x8GB $79SanDisk Extreme 64GB $72
WD Blue 1TB (2012) $30Corsair Vengeance LPX DDR4 3000 C15 2x8GB $95SanDisk Extreme 32GB $28
Seagate Barracuda 3TB (2016) $85G.SKILL Trident Z DDR4 3200 C14 4x16GB $649SanDisk Ultra Fit 32GB $16
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