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Pm991

NVMe Samsung 256GB

▲ 500 ▼

Release date ≈ Q4 2019.

Average Bench: 98.4% (270th of 1080)

Based on 4,948 user benchmarks.  Model: PM991 NVMe Samsung 256GB
Poor: 64%Average: 98.4% Great: 166%

Popular builds with this SSD

Excellent average bench

The Pm991 NVMe Samsung 256GB averaged just 1.6% lower than the peak scores attained by the group leaders. This is an excellent result which ranks the Pm991 NVMe Samsung 256GB near the top of the comparison list.

Strengths

Avg. 4K-64Thread Mixed IO Speed 226MB/s
Avg. Sequential Read Speed 844MB/s

Terrible consistency

The range of scores (95th - 5th percentile) for the Pm991 NVMe Samsung 256GB is 101%. This is a particularly wide range which indicates that the Pm991 NVMe Samsung 256GB performs inconsistently under varying real world conditions.

Weaknesses

Avg. Sustained Write Speed 152MB/s
Avg. Sequential Write Speed 273MB/s

Average Bench

(Based on 4,948 samples)
Rank 27098.4%
Min Avg Max
527 Read 844 1,186
68.6 Write 273 899
125 Mixed 313 883
62.5 SusWrite 152 370
86.4% 395 MB/s
Min Avg Max
17.5 4K Read 33.1 50.4
40.2 4K Write 87.1 135
18.3 4K Mixed 37.6 68.9
145% 52.6 MB/s
Min Avg Max
182 DQ Read 285 481
71 DQ Write 216 791
98.1 DQ Mixed 226 553
176% 242 MB/s
User Benchmarks BenchSequentialRandom 4kDeep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
151GB free (System drive)
Firmware: 25306039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 534 169 166 157 160 147 MB/s
120% Outstanding
Read 1,094
Write 791
Mixed 803
SusWrite 222
162% 727 MB/s
4K Read 33.8
4K Write 65.9
4K Mixed 45.3
144% 48.3 MB/s
DQ Read 464
DQ Write 300
DQ Mixed 506
344% 423 MB/s
28GB free (System drive)
Firmware: 25309039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 152 177 175 189 99 106 MB/s
85.9% Excellent
Read 862
Write 124
Mixed 165
SusWrite 150
70% 325 MB/s
4K Read 25.6
4K Write 65.7
4K Mixed 30.1
112% 40.5 MB/s
DQ Read 241
DQ Write 110
DQ Mixed 166
126% 172 MB/s
51GB free (System drive)
Firmware: 25311039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 98 87 84 83 84 86 MB/s
81.2% Excellent
Read 856
Write 97.6
Mixed 151
SusWrite 87
64% 298 MB/s
4K Read 29.4
4K Write 70.6
4K Mixed 30.2
121% 43.4 MB/s
DQ Read 122
DQ Write 94.8
DQ Mixed 69
62% 95.3 MB/s
35GB free (System drive)
Firmware: 25309039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 127 118 116 110 110 112 MB/s
79.9% Very good
Read 836
Write 123
Mixed 206
SusWrite 115
69% 320 MB/s
4K Read 20.8
4K Write 66.3
4K Mixed 26.9
101% 38 MB/s
DQ Read 241
DQ Write 135
DQ Mixed 141
117% 172 MB/s
35GB free (System drive)
Firmware: 25309039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 118 126 114 122 133 91 MB/s
76% Very good
Read 767
Write 154
Mixed 248
SusWrite 117
70% 322 MB/s
4K Read 23.7
4K Write 55.7
4K Mixed 26.5
99% 35.3 MB/s
DQ Read 229
DQ Write 116
DQ Mixed 164
124% 170 MB/s
120GB free (System drive)
Firmware: 25304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 131 131 130 136 142 156 MB/s
66.2% Good
Read 629
Write 118
Mixed 214
SusWrite 138
60% 275 MB/s
4K Read 12.7
4K Write 72.2
4K Mixed 17.9
80% 34.3 MB/s
DQ Read 242
DQ Write 134
DQ Mixed 157
125% 178 MB/s
59GB free (System drive)
Firmware: 25307039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 112 74 92 108 103 104 MB/s
64.2% Good
Read 596
Write 143
Mixed 164
SusWrite 98.7
54% 250 MB/s
4K Read 15.2
4K Write 66.7
4K Mixed 23.5
88% 35.1 MB/s
DQ Read 206
DQ Write 116
DQ Mixed 166
122% 163 MB/s
146GB free (System drive)
Firmware: 25304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 122 117 116 104 88 89 MB/s
62.2% Good
Read 637
Write 153
Mixed 203
SusWrite 106
60% 275 MB/s
4K Read 13.7
4K Write 51.2
4K Mixed 19
72% 28 MB/s
DQ Read 243
DQ Write 121
DQ Mixed 161
125% 175 MB/s
14GB free (System drive)
Firmware: 25311039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 58 56 51 47 44 48 MB/s
23.2% Poor
Read 355
Write 43.4
Mixed 96.6
SusWrite 50.6
29% 136 MB/s
4K Read 5.2
4K Write 6.5
4K Mixed 5.9
19% 5.87 MB/s
4,948 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 77,608,390 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 256GB Builds (Compare 3,018 builds) See popular component choices, score breakdowns and rankings
Gaming
Gaming 10%
Tree trunk
Desktop
Desktop 64%
Destroyer
Workstation
Workstation 9%
Tree trunk

System: Dell G3 3590

CPU
Core i5-9300HIntelBench 65%, 116,682 samples1,563x
Core i7-9750HIntelBench 73%, 328,182 samples1,454x
Core i7-9850HIntelBench 77%, 9,974 samples1x
GPU
UHD Graphics 630IntelBench 5%, 506,702 samples1,518x
GTX 1660-Ti (Mobile Max-Q)NvidiaBench 57%, 12,899 samples880x
GTX 1650 (Mobile)NvidiaBench 41%, 92,838 samples458x
SSD
NVMe Samsung 256GBPm991Bench 98%, 4,948 samples1x
RAM
HMA851S6JJR6N-VK 2x4GBUnknownBench 62%, 3,853 samples255x
HMA81GS6JJR8N-VK 2x8GBUnknownBench 74%, 13,906 samples188x
KKN2NM-MIE 2x4GBUnknownBench 59%, 2,182 samples179x
EDIT WITH CUSTOM PC BUILDER

Popular NVMe Samsung 256GB systems:

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 Frequently Asked Questions

Storage Devices FAQ
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The Best
CPUGPUSSD
Intel Core i5-13600K $210Nvidia RTX 4060 $285WD Black SN850X M.2 2TB $125
Intel Core i5-12600K $155Nvidia RTX 4060-Ti $389WD Black SN850X M.2 1TB $80
Intel Core i5-12400F $111Nvidia RTX 4070 $500Crucial T700 M.2 4TB $330
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