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Pm991a

NVMe Samsung 512GB

▲ 501 ▼

Release date ≈ Q4 2020.

Average Bench: 159% (144th of 1072)

Based on 3,717 user benchmarks.  Model: PM991a NVMe Samsung 512GB
Poor: 86%Average: 159% Great: 244%

Popular builds with this SSD

Outstanding average bench

The Pm991a NVMe Samsung 512GB averaged 58.8% higher than the peak scores attained by the group leaders. This is an excellent result which ranks the Pm991a NVMe Samsung 512GB near the top of the comparison list.

Strengths

Avg. 4K-64Thread Mixed IO Speed 640MB/s
Avg. 4K-64Thread Read Speed 892MB/s

Terrible consistency

The range of scores (95th - 5th percentile) for the Pm991a NVMe Samsung 512GB is 158%. This is a particularly wide range which indicates that the Pm991a NVMe Samsung 512GB performs inconsistently under varying real world conditions.

Weaknesses

Avg. Sustained Write Speed 485MB/s
Avg. 4K Random Write Speed 98.9MB/s
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Average Bench

(Based on 3,717 samples)
Rank 144159%
Min Avg Max
641 Read 1,144 1,582
124 Write 908 1,728
196 Mixed 826 1,506
101 SusWrite 485 799
188% 841 MB/s
Min Avg Max
20.1 4K Read 37.4 54.8
47.9 4K Write 98.9 163
25.3 4K Mixed 49.8 80.7
173% 62 MB/s
Min Avg Max
440 DQ Read 892 1,397
103 DQ Write 461 1,172
159 DQ Mixed 640 1,168
485% 664 MB/s
User Benchmarks BenchSequentialRandom 4kDeep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
408GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 1131 1234 1070 427 252 269 MB/s
179% Outstanding
Read 1,404
Write 1,334
Mixed 1154
SusWrite 731
259% 1,156 MB/s
4K Read 42
4K Write 92.1
4K Mixed 56.7
185% 63.6 MB/s
DQ Read 667
DQ Write 251
DQ Mixed 482
350% 467 MB/s
319GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 217 202 209 162 157 134 MB/s
125% Outstanding
Read 1,243
Write 400
Mixed 419
SusWrite 180
122% 561 MB/s
4K Read 30.5
4K Write 76.7
4K Mixed 36.8
134% 48 MB/s
DQ Read 724
DQ Write 293
DQ Mixed 519
382% 512 MB/s
334GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 145 196 194 148 170 194 MB/s
122% Outstanding
Read 1,079
Write 382
Mixed 237
SusWrite 174
102% 468 MB/s
4K Read 31.7
4K Write 90.3
4K Mixed 40.1
147% 54 MB/s
DQ Read 856
DQ Write 156
DQ Mixed 264
256% 426 MB/s
329GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 174 164 185 159 146 148 MB/s
105% Outstanding
Read 946
Write 195
Mixed 386
SusWrite 163
92% 422 MB/s
4K Read 20.6
4K Write 83.5
4K Mixed 32.4
117% 45.5 MB/s
DQ Read 834
DQ Write 138
DQ Mixed 246
242% 406 MB/s
57GB free (System drive)
Firmware: 26300039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 103 110 111 116 107 104 MB/s
85.3% Excellent
Read 902
Write 119
Mixed 217
SusWrite 108
72% 336 MB/s
4K Read 22
4K Write 54.2
4K Mixed 27.6
97% 34.6 MB/s
DQ Read 442
DQ Write 123
DQ Mixed 181
160% 249 MB/s
310GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 139 124 115 121 111 112 MB/s
85.3% Excellent
Read 793
Write 349
Mixed 298
SusWrite 120
86% 390 MB/s
4K Read 22.5
4K Write 53.4
4K Mixed 29.2
100% 35 MB/s
DQ Read 526
DQ Write 159
DQ Mixed 208
189% 298 MB/s
100GB free (System drive)
Firmware: 26303039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 127 122 114 117 112 110 MB/s
76.1% Very good
Read 961
Write 261
Mixed 230
SusWrite 117
85% 392 MB/s
4K Read 20
4K Write 32.9
4K Mixed 22.5
76% 25.1 MB/s
DQ Read 197
DQ Write 106
DQ Mixed 205
138% 170 MB/s
3,717 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 75,667,686 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 NVMe Samsung 512GB Builds (Compare 2,781 builds) See popular component choices, score breakdowns and rankings
Gaming
Gaming 13%
Tree trunk
Desktop
Desktop 82%
Aircraft carrier
Workstation
Workstation 13%
Tree trunk

System: Dell G15 5511

CPU
Core i7-11800HIntelBench 88%, 56,029 samples1,842x
Core i5-11400HIntelBench 80%, 35,470 samples503x
Gen Intel Core i5-11260H11thBench 72%, 2,929 samples432x
GPU
UHD GraphicsIntelBench 7%, 53,008 samples945x
RTX 3060 (Laptop)NvidiaBench 90%, 102,706 samples607x
UHD GraphicsIntelBench 4%, 25,082 samples509x
SSD
NVMe Samsung 512GBPm991aBench 159%, 3,717 samples307x
RAM
HMAA1GS6CJR6N-XN 2x8GBUnknownBench 65%, 26,875 samples775x
M471A1G44BB0-CWE 2x8GBSamsungBench 64%, 6,868 samples318x
4ATF1G64HZ-3G2E2 2x8GBUnknownBench 71%, 3,640 samples291x
EDIT WITH CUSTOM PC BUILDER

Popular NVMe Samsung 512GB systems:

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Welcome to our 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 value for money upgrades.

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Solid State Drive Rankings (Price vs Performance) April 2024 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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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?
How is the AS SSD read score calculated?
How is the AS SSD total score calculated?
ALL FAQs »

 Best User Rated
The Best.
CPUGPUSSD
Intel Core i5-13600K $279Nvidia RTX 4060 $300Crucial MX500 250GB $40
Intel Core i5-12400F $133Nvidia RTX 4060-Ti $385Samsung 850 Evo 120GB $80
Intel Core i5-12600K $182Nvidia RTX 4070 $409Samsung 860 Evo 250GB $52
HDDRAMUSB
Seagate Barracuda 1TB (2016) $39Corsair Vengeance LPX DDR4 3200 C16 2x8GB $40SanDisk Extreme 64GB $72
WD Blue 1TB (2012) $30Corsair Vengeance LPX DDR4 3000 C15 2x8GB $43SanDisk Extreme 32GB $28
Seagate Barracuda 2TB (2016) $51G.SKILL Trident Z DDR4 3200 C14 4x16GB $351SanDisk Ultra Fit 32GB $16
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