Average Bench: 79% (58th of 113)

Based on 612 user benchmarks.  Model: Corsair CM4X8GF2666C16K8 2x8GB

Good average bench

The Corsair CM4X8GF2666C16K8 2x8GB averaged 20.9% lower than the peak scores attained by the group leaders. This is an excellent result which ranks the Corsair CM4X8GF2666C16K8 2x8GB near the top of the comparison list.


Avg. 16 Core Read Bench 31.1GB/s
Avg. 16 Core Write Bench 30GB/s

Good consistency

The range of scores (95th - 5th percentile) for the Corsair CM4X8GF2666C16K8 2x8GB is 24.1%. This is a relatively narrow range which indicates that the Corsair CM4X8GF2666C16K8 2x8GB performs reasonably consistently under varying real world conditions.


Avg. 1 Core Read Bench 17.6GB/s
Avg. Physical RAM Latency 63.9ns

Average Bench

(Based on 612 samples)
Min Avg Max
25.3 MC Read 31.1 34.8
23.5 MC Write 30 35.2
19.2 MC Mixed 23 25.4
80.1% 28 GB/s
Min Avg Max
11.9 SC Read 17.6 20.2
18.1 SC Write 28.8 36.4
16.1 SC Mixed 23.5 27.3
66.5% 23.3 GB/s
Min Avg Max
55.6 Latency 63.9 80.9
62.6% 63.9 ns
User Benchmarks Bench Multi core Single core Latency
The fastest RAM (mainstream) averages a speed of 100%
2 of 4 slots used
16GB DIMM DDR4 clocked @ 2666 MHz
MC Read 32.6
MC Write 32.6
MC Mixed 22.7
84% 29.3 GB/s
SC Read 18.2
SC Write 34.9
SC Mixed 25.1
74% 26.1 GB/s
Latency 55.7
72% 55.7 ns
2 of 4 slots used
16GB DIMM DDR4 clocked @ 2666 MHz
MC Read 32
MC Write 29.4
MC Mixed 22.1
80% 27.8 GB/s
SC Read 19.3
SC Write 32
SC Mixed 25.5
73% 25.6 GB/s
Latency 57
70% 57 ns
2 of 2 slots used
16GB DIMM DDR4 clocked @ 2666 MHz
MC Read 31.5
MC Write 31.1
MC Mixed 22.8
81% 28.5 GB/s
SC Read 16.1
SC Write 31.1
SC Mixed 23.1
67% 23.4 GB/s
Latency 61.8
65% 61.8 ns
2 of 4 slots used
16GB DIMM DDR4 clocked @ 2133 MHz
MC Read 27.7
MC Write 27.4
MC Mixed 20.5
72% 25.2 GB/s
SC Read 16.2
SC Write 25.8
SC Mixed 20.9
60% 21 GB/s
Latency 69
58% 69 ns
612 MORE »

 Market Share (See Leaders)

The number of benchmark samples for this model as a percentage of all 45,724,727 RAM Kits tested.

Typical CM4X8GF2666C16K8 2x8GB Builds (Compare 2,793 builds) See popular component choices, score breakdowns and rankings.
Gaming 53%
Desktop 87%
Aircraft carrier
Workstation 45%

Motherboard: Asus ROG STRIX B360-H GAMING

EDIT WITH CUSTOM PC BUILDER Value: 59% - Above average Total price: $542

Popular CM4X8GF2666C16K8 2x8GB compatible motherboards:

How Fast Is Your RAM? (Bench your build) Size up your PC in less than a minute.

Welcome to our freeware PC speed test tool. UserBenchmark will test your PC and compare the results to other users with the same components. You can quickly size up your PC, identify hardware problems and explore the best upgrades.

UserBenchmark of the month

How it works

  • - Download and run UserBenchMark.
  • - CPU tests include: integer, floating and string.
  • - GPU tests include: six 3D game simulations.
  • - Drive tests include: read, write, sustained write and mixed IO.
  • - RAM tests include: single/multi core bandwidth and latency.
  • - SkillBench (space shooter) tests user input accuracy.
  • - Reports are generated and presented on userbenchmark.com.
  • - Identify the strongest components in your PC.
  • - See speed test results from other users.
  • - Compare your components to the current market leaders.
  • - Explore your best upgrade options with a virtual PC build.
  • - Compare your in-game FPS to other users with your hardware.
Memory Kit Rankings (Price vs Performance) September 2021 RAM Rankings.

We calculate effective RAM speed which measures performance for typical desktop users. Effective speed is adjusted by current cost per GB to yield value for money. Our calculated values are checked against thousands of individual user ratings. The customizable table below combines these factors to bring you the definitive list of top Memory Kits. [RAMPro]


Group Test Results

  • Best user rated - User sentiment trumps benchmarks for this comparison.
  • Best value for money - Value for money is based on real world performance.
  • Fastest real world speed - Real World Speed measures performance for typical consumers.


113 Memory Kits (Compared) Thousands of user benchmarks compiled into one comparison list.

See how consistently different RAM Kits perform with varying real world conditions. The charts also illustrate overall performance, popularity and rank.

 Frequently Asked Questions

 Best User Rated

The Best.
Intel Core i5-11600K $270Nvidia RTX 3060-Ti $400Crucial MX500 250GB $45
Intel Core i5-11400F $260Nvidia RTX 3070 $500Samsung 850 Evo 120GB $183
Intel Core i7-11700K $346Nvidia GTX 1660S (Super) $240Samsung 860 Evo 250GB $52
Seagate Barracuda 1TB (2016) $40Corsair Vengeance LPX DDR4 3200 C16 2x8GB $78SanDisk Extreme 64GB $72
WD Blue 1TB (2012) $35Corsair Vengeance LPX DDR4 3000 C15 2x8GB $77SanDisk Extreme 32GB $28
Seagate Barracuda 2TB (2016) $80G.SKILL Trident Z DDR4 3200 C14 4x16GB $649SanDisk Ultra Fit 32GB $16
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