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Pm991a

NVMe Samsung 512GB

▲ 501 ▼

Release date ≈ Q4 2020.

Average Bench: 159% (152nd of 1080)

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 152159%
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%
431GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 824 870 693 569 521 462 MB/s
236% Outstanding
Read 1,521
Write 1,734
Mixed 1,423
SusWrite 656
300% 1,334 MB/s
4K Read 57.7
4K Write 187
4K Mixed 86.2
297% 110 MB/s
DQ Read 1,186
DQ Write 729
DQ Mixed 677
580% 864 MB/s
430GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 1145 947 889 459 282 308 MB/s
212% Outstanding
Read 1,055
Write 1,172
Mixed 998
SusWrite 672
219% 974 MB/s
4K Read 44.1
4K Write 145
4K Mixed 70.1
233% 86.3 MB/s
DQ Read 1,390
DQ Write 1130
DQ Mixed 1,169
900% 1,230 MB/s
319GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 168 147 155 153 189 171 MB/s
120% Outstanding
Read 1200
Write 358
Mixed 326
SusWrite 164
111% 512 MB/s
4K Read 28.2
4K Write 70.8
4K Mixed 34.9
125% 44.6 MB/s
DQ Read 863
DQ Write 203
DQ Mixed 245
255% 437 MB/s
232GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 146 168 146 140 134 139 MB/s
110% Outstanding
Read 896
Write 226
Mixed 333
SusWrite 146
87% 400 MB/s
4K Read 28.6
4K Write 86
4K Mixed 38.3
138% 51 MB/s
DQ Read 858
DQ Write 189
DQ Mixed 218
239% 422 MB/s
65GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 124 138 114 103 100 115 MB/s
101% Outstanding
Read 1,070
Write 119
Mixed 217
SusWrite 116
82% 380 MB/s
4K Read 24.3
4K Write 59.4
4K Mixed 30
107% 37.9 MB/s
DQ Read 694
DQ Write 141
DQ Mixed 219
212% 351 MB/s
184GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 154 150 134 132 132 117 MB/s
92.5% Outstanding
Read 769
Write 343
Mixed 302
SusWrite 136
85% 387 MB/s
4K Read 26.6
4K Write 58.5
4K Mixed 32.6
113% 39.2 MB/s
DQ Read 668
DQ Write 163
DQ Mixed 125
167% 319 MB/s
285GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 150 184 155 170 175 175 MB/s
80% Very good
Read 699
Write 251
Mixed 252
SusWrite 168
75% 342 MB/s
4K Read 19.1
4K Write 49.4
4K Mixed 22.4
84% 30.3 MB/s
DQ Read 605
DQ Write 120
DQ Mixed 435
300% 387 MB/s
20GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 72 86 85 74 79 58 MB/s
67.3% Good
Read 567
Write 110
Mixed 109
SusWrite 75.6
46% 216 MB/s
4K Read 24.7
4K Write 42
4K Mixed 27.1
94% 31.3 MB/s
DQ Read 437
DQ Write 49.9
DQ Mixed 107
113% 198 MB/s
3,717 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 76,509,829 SSDs tested

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CHOOSE A COMPONENT:

CPU GPU SSD HDD RAM MBD
Typical NVMe Samsung 512GB Builds (Compare 2,838 builds) See popular component choices, score breakdowns and rankings
Gaming
Gaming 13%
Tree trunk
Desktop
Desktop 83%
Aircraft carrier
Workstation
Workstation 13%
Tree trunk

System: Dell G15 5511

CPU
Core i7-11800HIntelBench 88%, 79,827 samples1,869x
Core i5-11400HIntelBench 80%, 35,470 samples515x
Gen Intel Core i5-11260H11thBench 72%, 2,929 samples450x
GPU
UHD GraphicsIntelBench 7%, 53,008 samples963x
RTX 3060 (Laptop)NvidiaBench 90%, 102,706 samples613x
UHD GraphicsIntelBench 4%, 25,082 samples530x
SSD
NVMe Samsung 512GBPm991aBench 159%, 3,717 samples311x
RAM
HMAA1GS6CJR6N-XN 2x8GBUnknownBench 65%, 26,875 samples789x
M471A1G44BB0-CWE 2x8GBSamsungBench 64%, 6,868 samples323x
4ATF1G64HZ-3G2E2 2x8GBUnknownBench 71%, 3,640 samples296x
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Popular NVMe Samsung 512GB systems:

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