6 Cores, 6 Threads
@2.8GHz Coffee Lake (2017)

4 Cores, 4 Threads
@3.5GHz Skylake (2015)

Real World Speed
Performance profile from 112,762 user samples
6,559 User Benchmarks
Best Bench: 96% Base clock 2.8 GHz, turbo 3.85 GHz (avg)
Worst Bench: 87% Base clock 2.8 GHz, turbo 0.8 GHz (avg)
Poor: 87% Great: 96%
SPEED RANK: 25th / 1052
Gaming 92%
Nuclear submarine
Desktop 89%
Aircraft carrier
Workstation 67%
Battle cruiser
106,203 User Benchmarks
Best Bench: 106% Base clock 3.5 GHz, turbo 4.8 GHz (avg)
Worst Bench: 69% Base clock 3.5 GHz, turbo 0.75 GHz (avg)
Poor: 69% Great: 106%
SPEED RANK: 34th / 1052
Gaming 88%
Aircraft carrier
Desktop 86%
Aircraft carrier
Workstation 54%
Effective Speed
Effective CPU Speed
92.4 % Slightly faster effective speed.
87.9 %
SC Mixed
Avg. Single Core Mixed Speed
120 Pts 121 Pts +1%
QC Mixed
Avg. Quad Core Mixed Speed
470 Pts +3% 455 Pts
MC Mixed
Avg. Multi Core Mixed Speed
686 Pts Much faster multi-core speed.
469 Pts
SC Mixed
OC Single Core Mixed Speed
126 Pts 145 Pts Faster OC single-core speed.
QC Mixed
OC Quad Core Mixed Speed
489 Pts 557 Pts Slightly faster OC quad-core speed.
MC Mixed
OC Multi Core Mixed Speed
724 Pts Faster OC multi-core speed.
565 Pts
Market Share
Based on 7,889,714 CPUs tested.
Market Share
Market Share (trailing 30 days)
0.88 % 0.88 %
Value For Money
111 % Slightly better value.
97 %
User Rating
UBM User Rating
114 % More popular.
89 %
Price (score)
$179 Cheaper.
5 Months Hugely more recent.
31 Months
Thermal Design Power (TDP)
65 Watts More energy efficient.
91 Watts
CPU Processing Cores
6 cores Much higher core count.
4 cores
CPU Processing Threads
6 threads Much higher thread count.
4 threads
Manufacturing process
14 nm 14 nm
Base Clock
Base Clock Speed
2.8 GHz 3.5 GHz Faster base frequency.
Turbo Clock
Turbo Clock Speed
4 GHz +3% 3.9 GHz
SC Int
Single Core Integer Speed
122 Pts 140 Pts Slightly faster single-core int speed.
SC Float
Single Core Floating Point Speed
129 Pts 149 Pts Faster single-core fp speed.
QC Int
Quad Core Integer Speed
476 Pts 545 Pts Slightly faster quad-core int speed.
QC Float
Quad Core Floating Point Speed
504 Pts 582 Pts Faster quad-core fp speed.
MC Int
Multi Core Integer Speed
703 Pts Faster multi-core int speed.
548 Pts
MC Float
Multi Core Floating Point Speed
746 Pts Faster multi-core fp speed.
583 Pts
CPU Architecture
Coffee Lake (2017) Skylake (2015)
Motherboard Socket
Integrated Graphics
UHD 630 HD 530
Launch Date
Launch Date
Q4'17 Q3'15
9 MB 6 MB SmartCache
Instruction Set Extensions
Instruction Set Extensions
SSE4.1/4.2, AVX2 SSE4.1/4.2, AVX 2.0
Recommended Price
Recommended Customer Price
N/A $242.00 - $243.00
Thermal Solution Specification
Thermal Solution Specification
PCG 2015C (65W) PCG 2015D (130W)
Memory Types
Memory Types
DDR4-2666 DDR4-1866/2133, DDR3L-1333/1600 @ 1.35V
Processor Graphics
Processor Graphics ‡
Intel® UHD Graphics 630 Intel® HD Graphics 530
Graphics Max Dynamic Frequency
Graphics Max Dynamic Frequency
1.05 GHz 1.15 GHz
Intel® TSX-NI
No Yes
PCI Express Configurations
PCI Express Configurations ‡
Up to 1x16 or 2x8 or 1x8+2x4 Up to 1x16, 2x8, 1x8+2x4

More specs » More specs »

The i5-8400 is a competitively priced hex-core processor from Intel’s 8th generation of Core processors (Coffee Lake). Along with the release of the unlocked i5-8600K, this is the first time that six-core processors have featured in the i5 line-up. Like the other Coffee Lake processors, the i5-8400 is based upon an improved version of Intel’s 14nm architecture which featured in both Skylake and Kaby Lake. Early benchmarks reveal that for average quad core usage (most games employ a maximum of four cores) the i5-8400 performs way above its pay grade. It achieves quad core mixed speeds close to Intel’s outgoing 2017 flagship the $300, quad-core, 8 thread i7-7700k, which to date has been a strong favourite for high-end gaming setups. On paper, the i5-8400 has a base clock of 2.8 GHz (Intel are significantly downplaying the performance of this SKU by giving it a relatively low nominal base clock), an all core boost of 3.8 GHz (this is the effective base clock figure that counts) and a single core boost of 4 GHz. This compares reasonably well to the i5-8600K which has a base clock of 3.6 GHz, all core boost of 4.1 GHz and a single core boost of 4.3 GHz. The i5-8400 also features 9MB of L3 cache and an energy-thrifty TDP of 65W. Priced at under $190, the i5-8400 offers fantastic value for money. Unfortunately, like the other Coffee Lake processors, the i5-8400 will require a new 300 series motherboard, and at the time of writing, the only available version is Intel’s high-end Z370 which isn't an ideal pairing for the i5-8400. The Z series motherboards are designed to cater for the unlocked and overclockable "K" SKUs. Cheaper 300 series motherboards will be available in 2018 at which time the 8400 will offer even better value for money. [Oct '17 CPUPro]


The Intel Core i5-6600K is based on the new "Skylake" 14nm manufacturing process. Sporting 4 physical cores with base/turbo clocks of 3.5/3.9 GHz the 6600K and its predecessor, the 4690K share the same basic configuration and disappointingly, offer similar performance. Comparing the 6600K and 6700K shows that the 6700K has faster multi and single core performance. The improved multi core performance is due to Hyperthreading which is the key differentiator for the i7-6700K. The gap in single core performance can largely be eliminated by overclocking the i5-6600K so although the stock effective speed is significantly higher on the 6700K, this gap diminishes significantly when both processors are overclocked. At a 30% discount, the 6600K is the better value gaming CPU. [Aug '15 CPUPro]


Processor Rankings (Price vs Performance) March 2018 CPU Rankings.

We calculate effective speed which measures real world performance for typical consumers. Effective speed is adjusted by current prices to yield a value for money rating which is geared towards gamers. 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 CPUs. [CPUPro]


Group Test Results

  • Best user rated - User sentiment trumps benchmarks for this comparison.
  • Fastest real world speed - Real World Speed measures performance for typical consumers.
  • Best value for money - Value for money is based on real world performance and price.
How Fast Is Your CPU? (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.

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  • - CPU tests include: integer, floating and string.
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  • - RAM tests include: single/multi core bandwidth and latency.
  • - Reports are generated and presented on
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  • - Compare your components to the highest voted in class.
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Intel Core i7-7700K $290Nvidia GTX 1060-6GB $335Samsung 850 Evo 500GB $149
AMD Ryzen 5 1600 $189AMD RX 480 $400Samsung 850 Pro 256GB $129
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Seagate Barracuda 3TB (2016) $75G.SKILL Trident Z DDR4 3200 C14 4x16GB $931SanDisk Extreme 32GB $23
Seagate Barracuda 7200.14 1TB $51Corsair Vengeance LPX DDR4 3200 C16 2x8GB $205SanDisk Extreme 16GB $18
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