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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
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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%
10GB free (System drive)
Firmware: 25311039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 41 46 46 49 50 48 MB/s
429% Outstanding
Read 4,903
Write 47.2
Mixed 101
SusWrite 46.4
265% 1,274 MB/s
4K Read 572
4K Write 2.5
4K Mixed 2.6
871% 192 MB/s
190GB free (System drive)
Firmware: 25306039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 813 505 158 176 164 181 MB/s
124% Outstanding
Read 749
Write 663
Mixed 624
SusWrite 333
133% 592 MB/s
4K Read 37.4
4K Write 74.8
4K Mixed 48.6
158% 53.6 MB/s
DQ Read 479
DQ Write 597
DQ Mixed 552
412% 542 MB/s
58GB free (System drive)
Firmware: 25311039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 121 123 130 137 132 132 MB/s
96.6% Outstanding
Read 990
Write 125
Mixed 221
SusWrite 129
79% 366 MB/s
4K Read 30.6
4K Write 85.5
4K Mixed 34.1
135% 50.1 MB/s
DQ Read 246
DQ Write 108
DQ Mixed 166
126% 173 MB/s
71GB free (System drive)
Firmware: 25305039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 110 177 189 129 164 140 MB/s
89.5% Excellent
Read 923
Write 83.7
Mixed 132
SusWrite 151
69% 322 MB/s
4K Read 28.4
4K Write 67.8
4K Mixed 30.7
118% 42.3 MB/s
DQ Read 246
DQ Write 75
DQ Mixed 127
102% 149 MB/s
8GB free (System drive)
Firmware: 25307039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 79 77 70 68 64 61 MB/s
88.1% Excellent
Read 974
Write 74
Mixed 162
SusWrite 69.7
68% 320 MB/s
4K Read 29.3
4K Write 76.3
4K Mixed 30.5
124% 45.4 MB/s
DQ Read 230
DQ Write 92
DQ Mixed 127
103% 150 MB/s
10GB free (System drive)
Firmware: 25306039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 69 58 54 52 51 51 MB/s
77.5% Very good
Read 778
Write 99.2
Mixed 149
SusWrite 55.8
58% 270 MB/s
4K Read 27.8
4K Write 70.9
4K Mixed 29.4
117% 42.7 MB/s
DQ Read 247
DQ Write 77.9
DQ Mixed 120
99% 148 MB/s
157GB free (System drive)
Firmware: 25305039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 123 120 114 123 117 115 MB/s
76.6% Very good
Read 700
Write 163
Mixed 190
SusWrite 119
64% 293 MB/s
4K Read 26.7
4K Write 75.5
4K Mixed 30.2
119% 44.1 MB/s
DQ Read 138
DQ Write 84.2
DQ Mixed 31.3
45% 84.3 MB/s
107GB free (System drive)
Firmware: 25304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 121 112 114 110 106 107 MB/s
71.8% Very good
Read 551
Write 144
Mixed 173
SusWrite 112
53% 245 MB/s
4K Read 26.3
4K Write 71.1
4K Mixed 28.6
114% 42 MB/s
DQ Read 247
DQ Write 121
DQ Mixed 162
126% 177 MB/s
4,948 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 76,509,615 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 2,953 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 samples1,536x
Core i7-9750HIntelBench 73%, 328,182 samples1,416x
Core i7-9850HIntelBench 77%, 9,974 samples1x
GPU
UHD Graphics 630IntelBench 5%, 506,702 samples1,482x
GTX 1660-Ti (Mobile Max-Q)NvidiaBench 57%, 12,899 samples865x
GTX 1650 (Mobile)NvidiaBench 41%, 92,838 samples447x
SSD
NVMe Samsung 256GBPm991Bench 98%, 4,948 samples1x
RAM
HMA851S6JJR6N-VK 2x4GBUnknownBench 62%, 3,853 samples251x
HMA81GS6JJR8N-VK 2x8GBUnknownBench 74%, 13,906 samples182x
KKN2NM-MIE 2x4GBUnknownBench 59%, 2,182 samples174x
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Popular NVMe Samsung 256GB systems:

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