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Pm991a

NVMe Samsung 128GB

▲ 500 ▼

Release date ≈ Q1 2021.

Average Bench: 105% (240th of 1080)

Based on 253 user benchmarks.  Model: PM991a NVMe Samsung 128GB
Poor: 56%Average: 105% Great: 178%

Popular builds with this SSD

Outstanding average bench

The Pm991a NVMe Samsung 128GB averaged 5.1% higher than the peak scores attained by the group leaders. This is an excellent result which ranks the Pm991a NVMe Samsung 128GB near the top of the comparison list.

Strengths

Avg. 4K-64Thread Mixed IO Speed 346MB/s
Avg. 4K-64Thread Read Speed 550MB/s

Terrible consistency

The range of scores (95th - 5th percentile) for the Pm991a NVMe Samsung 128GB is 122%. This is a particularly wide range which indicates that the Pm991a NVMe Samsung 128GB performs inconsistently under varying real world conditions.

Weaknesses

Avg. Sustained Write Speed 170MB/s
Avg. Sequential Write Speed 427MB/s

Average Bench

(Based on 253 samples)
Rank 240105%
Min Avg Max
476 Read 901 1,346
97.9 Write 427 1,132
179 Mixed 465 1,097
81.8 SusWrite 170 286
108% 491 MB/s
Min Avg Max
12.8 4K Read 30.9 53.6
20 4K Write 67.7 134
14.9 4K Mixed 36.8 72
130% 45.1 MB/s
Min Avg Max
160 DQ Read 550 954
79.4 DQ Write 290 872
114 DQ Mixed 346 840
277% 395 MB/s
User Benchmarks BenchSequentialRandom 4kDeep queue 4k
The fastest SSD (mainstream) averages a speed of 100%
100GB free
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 633 211 218 219 187 164 MB/s
154% Outstanding
Read 1,450
Write 1,154
Mixed 1,185
SusWrite 272
226% 1,015 MB/s
4K Read 38.4
4K Write 79
4K Mixed 50.3
164% 55.9 MB/s
DQ Read 719
DQ Write 551
DQ Mixed 617
466% 629 MB/s
64GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 479 192 180 187 209 175 MB/s
85.8% Excellent
Read 901
Write 644
Mixed 539
SusWrite 237
129% 580 MB/s
4K Read 21.8
4K Write 46
4K Mixed 30.3
96% 32.7 MB/s
DQ Read 132
DQ Write 91.1
DQ Mixed 120
87% 114 MB/s
50GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 132 124 121 128 119 127 MB/s
73.9% Very good
Read 810
Write 144
Mixed 216
SusWrite 125
70% 324 MB/s
4K Read 21.9
4K Write 30.4
4K Mixed 22.5
78% 24.9 MB/s
DQ Read 323
DQ Write 112
DQ Mixed 194
149% 210 MB/s
10GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 102 83 71 69 67 67 MB/s
63.5% Good
Read 630
Write 132
Mixed 221
SusWrite 76.3
58% 265 MB/s
4K Read 15.3
4K Write 29.6
4K Mixed 16.1
60% 20.3 MB/s
DQ Read 564
DQ Write 133
DQ Mixed 275
221% 324 MB/s
27GB free (System drive)
Firmware: 26304039 Max speed: PCIe 16,000 MB/s
SusWrite @10s intervals: 122 99 99 99 95 97 MB/s
61.1% Good
Read 566
Write 203
Mixed 188
SusWrite 102
58% 265 MB/s
4K Read 13.6
4K Write 21.9
4K Mixed 16.6
54% 17.4 MB/s
DQ Read 472
DQ Write 228
DQ Mixed 137
158% 279 MB/s
253 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 77,472,751 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 128GB Builds (Compare 407 builds) See popular component choices, score breakdowns and rankings
Gaming
Gaming 6%
Tree trunk
Desktop
Desktop 39%
Jet ski
Workstation
Workstation 6%
Tree trunk

System: Dell Latitude 3120

CPU
Pentium Silver N6000IntelBench 34%, 1,823 samples288x
Celeron N5100IntelBench 34%, 996 samples119x
GPU
UHD GraphicsIntelBench 4%, 2,177 samples288x
UHD GraphicsIntelBench 4%, 2,226 samples119x
SSD
NVMe Samsung 128GBPm991aBench 105%, 253 samples102x
RAM
HCNNNBKMMLXR-NEE 2x4GBHynixBench 44%, 239 samples199x
4ATF51264HZ-3G2J1 1x4GBMicronBench 35%, 7,475 samples66x
U6E3S4AA-MGCR 2x4GBSamsungBench 41%, 142 samples51x
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Popular NVMe Samsung 128GB systems:

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