Intel Core i7 7800X vs i5 9400F

We compared two 6-core desktop CPUs: the 3.5 GHz Intel Core i7 7800X against the 2.9 GHz i5 9400F. On this page, you'll find out which processor has better performance in benchmarks, games and other useful information.


General overview and comparison of the processors
Single-Core Performance
Performance in single-threaded apps and benchmarks
Measure performance when all cores are involved
Power Efficiency
The efficiency score of electricity consumption
NanoReview Final Score
Generic CPU rating

Key Differences

What are the key differences between 9400F and 7800X
Advantages of Intel Core i7 7800X
  • Unlocked multiplier
  • Supports quad-channel memory
  • Around 37.87 GB/s (91%) higher theoretical memory bandwidth
Advantages of Intel Core i5 9400F
  • Consumes up to 54% less energy than the Core i7 7800X – 65 vs 140 Watt
  • Newer - released 1-year and 8-months later
  • Has 1 MB larger L3 cache size
  • 2% higher Turbo Boost frequency (4.1 GHz vs 4 GHz)


Comparing the performance of CPUs in benchmarks
Cinebench R23 (Single-Core)
Cinebench R23 (Multi-Core)
Passmark CPU (Single-Core)
Passmark CPU (Multi-Core)
Geekbench 5 (Single-Core)
Geekbench 5 (Multi-Core)
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Full technical specification of Intel Core i7 7800X and i5 9400F


Vendor Intel Intel
Released May 30, 2017 January 7, 2019
Type Desktop Desktop
instruction set x86-64 x86-64
Codename Skylake Coffee Lake
Model number i7-7800X i5-9400F
Socket LGA-2066 LGA-1151
Integrated GPU No No


Cores 6 6
Threads 12 6
Base Frequency 3.5 GHz 2.9 GHz
Turbo Boost Frequency 4 GHz 4.1 GHz
Bus frequency 100 MHz 100 MHz
Multiplier 35x 29x
Bus Bandwidth 8 GT/s 8 GT/s
L1 Cache 64K (per core) 64K (per core)
L2 Cache 1MB (per core) 256K (per core)
L3 Cache 8MB (shared) 9MB (shared)
Unlocked Multiplier Yes No


Fabrication process 14 nm 14 nm
TDP 140 W 65 W
Max. temperature 100°C 100°C

Memory support

Memory types DDR4-2400 DDR4-2666
Memory Size 128 GB 128 GB
Max. Memory Channels 4 2
Max. Memory Bandwidth 79.47 GB/s 41.6 GB/s
ECC Support No No


Official site Intel Core i7 7800X official page Intel Core i5 9400F official page
PCI Express Version 3.0 3.0
PCI Express Lanes 28 16
Extended instructions SSE4.1, SSE4.2, AVX-2, AVX-512 SSE4.1, SSE4.2, AVX-2

Cast your vote

Choose between two processors
3 (60%)
2 (40%)
Total votes: 5


So which CPU will you choose: Intel Core i5 9400F or i7 7800X?