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Nvme

PM991a Samsung 512GB

▲ 500 ▼

Release date ≈ Q1 2021.

Average Bench: 132% (183rd of 1080)

Based on 1,958 user benchmarks.  Model: NVMe PM991a NVMe Samsung 512GB
Poor: 71%Average: 132% Great: 237%

Popular builds with this SSD

Outstanding average bench

The Nvme PM991a Samsung 512GB averaged 32.4% higher than the peak scores attained by the group leaders. This is an excellent result which ranks the Nvme PM991a Samsung 512GB near the top of the comparison list.

Strengths

Avg. 4K-64Thread Mixed IO Speed 390MB/s
Avg. 4K-64Thread Read Speed 658MB/s

Terrible consistency

The range of scores (95th - 5th percentile) for the Nvme PM991a Samsung 512GB is 166%. This is a particularly wide range which indicates that the Nvme PM991a Samsung 512GB performs inconsistently under varying real world conditions.

Weaknesses

Avg. Sustained Write Speed 392MB/s
Avg. 4K-64Thread Write Speed 283MB/s
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Average Bench

(Based on 1,958 samples)
Rank 183132%
Min Avg Max
580 Read 1,028 1,624
112 Write 632 1,688
181 Mixed 636 1,519
95.6 SusWrite 392 773
150% 672 MB/s
Min Avg Max
16.8 4K Read 34.2 54.8
27.2 4K Write 85.4 163
18.9 4K Mixed 41.9 77.9
151% 53.8 MB/s
Min Avg Max
221 DQ Read 658 1,274
89.9 DQ Write 283 989
132 DQ Mixed 390 1,063
310% 444 MB/s
User Benchmarks BenchSequentialRandom 4kDeep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
401GB free (System drive)
Firmware: 26302039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 1632 1657 225 185 338 355 MB/s
226% Outstanding
Read 1,616
Write 1,726
Mixed 1525
SusWrite 732
315% 1,400 MB/s
4K Read 51.7
4K Write 154
4K Mixed 75.4
256% 93.6 MB/s
DQ Read 1,065
DQ Write 612
DQ Mixed 671
544% 783 MB/s
313GB free
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 1751 1405 324 299 331 322 MB/s
209% Outstanding
Read 1,583
Write 1,773
Mixed 1,521
SusWrite 739
316% 1,404 MB/s
4K Read 42.1
4K Write 104
4K Mixed 58.2
193% 68.1 MB/s
DQ Read 1,044
DQ Write 795
DQ Mixed 905
681% 915 MB/s
295GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 706 831 687 1087 563 339 MB/s
174% Outstanding
Read 1,297
Write 1,213
Mixed 1,110
SusWrite 702
243% 1,081 MB/s
4K Read 38.6
4K Write 113
4K Mixed 50.4
183% 67.2 MB/s
DQ Read 729
DQ Write 303
DQ Mixed 58.1
164% 363 MB/s
153GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 171 130 113 122 110 118 MB/s
116% Outstanding
Read 1,086
Write 237
Mixed 237
SusWrite 127
91% 422 MB/s
4K Read 26.5
4K Write 101
4K Mixed 36.5
140% 54.7 MB/s
DQ Read 864
DQ Write 122
DQ Mixed 276
257% 420 MB/s
39GB free (System drive)
Firmware: 26303039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 125 110 95 94 89 93 MB/s
106% Outstanding
Read 793
Write 254
Mixed 246
SusWrite 101
76% 349 MB/s
4K Read 34.8
4K Write 113
4K Mixed 38.1
161% 62 MB/s
DQ Read 765
DQ Write 116
DQ Mixed 191
203% 357 MB/s
257GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 150 160 165 185 161 157 MB/s
94.9% Outstanding
Read 879
Write 292
Mixed 330
SusWrite 163
91% 416 MB/s
4K Read 14.5
4K Write 91.3
4K Mixed 23.4
100% 43.1 MB/s
DQ Read 694
DQ Write 186
DQ Mixed 283
249% 388 MB/s
156GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 117 124 124 123 126 118 MB/s
89.1% Excellent
Read 946
Write 126
Mixed 219
SusWrite 122
76% 353 MB/s
4K Read 30.4
4K Write 71.8
4K Mixed 22.6
113% 41.6 MB/s
DQ Read 348
DQ Write 115
DQ Mixed 200
156% 221 MB/s
1,958 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 76,509,716 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 512GB Builds (Compare 10,377 builds) See popular component choices, score breakdowns and rankings
Gaming
Gaming 124%
UFO
Desktop
Desktop 98%
Nuclear submarine
Workstation
Workstation 123%
UFO

System: Dell XPS 8940

CPU
Core i7-11700Intel  $190Bench 98%, 20,430 samples4,528x
Core i7-10700Intel  $235Bench 93%, 71,010 samples1,880x
Core i5-11400Intel  $117Bench 94%, 24,459 samples1,176x
GPU
RTX 3060-TiNvidia  $340Bench 128%, 442,467 samples2,464x
UHD Graphics 750IntelBench 7%, 15,464 samples1,103x
RTX 3060Nvidia  $256Bench 100%, 447,556 samples1,011x
SSD
PM991a Samsung 512GBNvmeBench 132%, 1,958 samples1x
RAM
HMAA1GU6CJR6N-XN 2x8GBUnknownBench 65%, 1,864 samples661x
M378A2G43AB3-CWE 2x16GBUnknownBench 79%, 764 samples548x
M378A1G44AB0-CWE 2x8GBUnknownBench 63%, 886 samples400x
EDIT WITH CUSTOM PC BUILDER Value: 96% - Outstanding Total price: $530

Popular PM991a Samsung 512GB systems:

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 Frequently Asked Questions

Storage Devices FAQ
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The Best
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Intel Core i5-13600K $235Nvidia RTX 4070 $499Crucial T700 M.2 4TB $342
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