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Nvme

PM991a Samsung 256GB

▲ 500 ▼

Release date ≈ Q1 2021.

Average Bench: 118% (192nd of 1072)

Based on 1,499 user benchmarks.  Model: NVMe PM991a NVMe Samsung 256GB
Poor: 57%Average: 118% Great: 205%

Popular builds with this SSD

Outstanding average bench

The Nvme PM991a Samsung 256GB averaged 18.5% higher than the peak scores attained by the group leaders. This is an excellent result which ranks the Nvme PM991a Samsung 256GB near the top of the comparison list.

Strengths

Avg. 4K-64Thread Mixed IO Speed 353MB/s
Avg. 4K-64Thread Read Speed 545MB/s

Terrible consistency

The range of scores (95th - 5th percentile) for the Nvme PM991a Samsung 256GB is 148%. This is a particularly wide range which indicates that the Nvme PM991a Samsung 256GB performs inconsistently under varying real world conditions.

Weaknesses

Avg. Sustained Write Speed 256MB/s
Avg. Sequential Write Speed 488MB/s
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Average Bench

(Based on 1,499 samples)
Rank 192118%
Min Avg Max
495 Read 979 1,508
79.2 Write 488 1,153
149 Mixed 516 1,190
80.3 SusWrite 256 535
124% 560 MB/s
Min Avg Max
14.5 4K Read 33.7 51.6
31.6 4K Write 87 152
14.8 4K Mixed 39.6 71.9
148% 53.4 MB/s
Min Avg Max
199 DQ Read 545 883
78.2 DQ Write 287 1,020
123 DQ Mixed 353 815
279% 395 MB/s
User Benchmarks BenchSequentialRandom 4kDeep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
190GB free (System drive)
Firmware: 26304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 764 854 416 173 147 182 MB/s
127% Outstanding
Read 1,009
Write 941
Mixed 913
SusWrite 423
184% 821 MB/s
4K Read 42.6
4K Write 89.6
4K Mixed 54.5
182% 62.2 MB/s
DQ Read 77.2
DQ Write 105
DQ Mixed 60.2
54% 80.7 MB/s
144GB free (System drive)
Firmware: 26304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 150 133 142 142 130 160 MB/s
110% Outstanding
Read 964
Write 250
Mixed 266
SusWrite 143
88% 406 MB/s
4K Read 35.5
4K Write 103
4K Mixed 40.4
160% 59.7 MB/s
DQ Read 484
DQ Write 143
DQ Mixed 201
178% 276 MB/s
141GB free (System drive)
Firmware: 26304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 188 163 155 144 144 128 MB/s
105% Outstanding
Read 826
Write 163
Mixed 194
SusWrite 153
72% 334 MB/s
4K Read 33.9
4K Write 107
4K Mixed 40.3
160% 60.3 MB/s
DQ Read 485
DQ Write 156
DQ Mixed 180
170% 274 MB/s
125GB free (System drive)
Firmware: 26304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 139 135 136 142 171 184 MB/s
89.5% Excellent
Read 934
Write 151
Mixed 256
SusWrite 151
81% 373 MB/s
4K Read 29.4
4K Write 69.9
4K Mixed 18
105% 39.1 MB/s
DQ Read 390
DQ Write 168
DQ Mixed 79.9
112% 213 MB/s
53GB free (System drive)
Firmware: 26304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 84 90 88 88 91 86 MB/s
86% Excellent
Read 812
Write 93.9
Mixed 158
SusWrite 87.8
62% 288 MB/s
4K Read 30
4K Write 67.7
4K Mixed 28.4
118% 42 MB/s
DQ Read 480
DQ Write 85.3
DQ Mixed 147
143% 237 MB/s
141GB free (System drive)
Firmware: 26304039 Max speed: PCIe 5,000 MB/s
SusWrite @10s intervals: 135 131 147 139 135 133 MB/s
74.8% Very good
Read 723
Write 190
Mixed 196
SusWrite 136
68% 311 MB/s
4K Read 18.2
4K Write 59.8
4K Mixed 17.2
81% 31.7 MB/s
DQ Read 482
DQ Write 116
DQ Mixed 252
197% 283 MB/s
1,499 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 73,438,433 SSDs tested

Custom PC Builder (Start a new build) Build your perfect PC: compare component prices, popularity, speed and value for money

CHOOSE A COMPONENT:

CPU GPU SSD HDD RAM MBD
Typical PM991a Samsung 256GB Builds (Compare 3,435 builds) See popular component choices, score breakdowns and rankings
Gaming
Gaming 13%
Tree trunk
Desktop
Desktop 74%
Battleship
Workstation
Workstation 12%
Tree trunk

System: Dell Inspiron 15 3511

CPU
Core i5-1135G7IntelBench 69%, 36,962 samples1,635x
Core i3-1115G4IntelBench 51%, 18,815 samples823x
Core i7-1165G7IntelBench 66%, 51,565 samples513x
GPU
Iris XeIntelBench 14%, 144,774 samples2,025x
UHD GraphicsIntelBench 9%, 18,212 samples856x
UHD G1IntelBench 5%, 68,603 samples431x
SSD
PM991a Samsung 256GBNvmeBench 118%, 1,499 samples1x
RAM
HMAA1GS6CJR6N-XN 1x8GBUnknownBench 37%, 6,851 samples968x
M471A1G44BB0-CWE 1x8GBSamsungBench 31%, 4,202 samples330x
HMAA1GS6CJR6N-XN 2x8GBUnknownBench 70%, 13,540 samples274x
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Popular PM991a Samsung 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

  • - 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
  • - SkillBench (space shooter) tests user input accuracy
  • - 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
Solid State Drive Rankings (Price vs Performance) December 2023 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]

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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.

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Speed Comparisons

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1072 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

Storage Devices FAQ
What is sustained sequential write speed?
What’s the difference between SLC, MLC and TLC?
What is 3D XPoint and how fast is it?
What’s the difference between SATA, PCIe and NVMe?
What’s the difference between NAND and V-NAND?
What is sequential write speed?
What is sequential read speed?
What is incompressible data?
What is queue depth?
Solid State Drives
What is the SSD value for money rating?
What is 4K 64 thread write speed?
Can CPU power saving states (C1,C2,C3) impact SSD speed?
What is the effective SSD speed index?
How is the AS SSD write score calculated?
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ALL FAQs »

 Best User Rated
The Best.
CPUGPUSSD
Intel Core i5-13600K $270Nvidia RTX 4060 $295Crucial MX500 250GB $30
Intel Core i5-12400F $146Nvidia RTX 4060-Ti $360Samsung 850 Evo 120GB $80
Intel Core i5-12600K $189Nvidia RTX 3060-Ti $340Samsung 860 Evo 250GB $49
HDDRAMUSB
Seagate Barracuda 1TB (2016) $40Corsair Vengeance LPX DDR4 3200 C16 2x8GB $42SanDisk Extreme 64GB $72
WD Blue 1TB (2012) $30Corsair Vengeance LPX DDR4 3000 C15 2x8GB $43SanDisk Extreme 32GB $28
Seagate Barracuda 2TB (2016) $50G.SKILL Trident Z DDR4 3200 C14 4x16GB $357SanDisk Ultra Fit 32GB $16
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