CPU Comparison

Intel Core i5-8400 vs Intel Core i5-9400

A side-by-side comparison of specs, performance and value. The Intel Core i5-8400 is a landmark mainstream desktop processor that fundamentally shifted the budget CPU market by bringing six physical cores to the i5 tier for the first time.

Top pick
Intel · Core i5
Intel Core i5-8400
6C / 6T4 GHz65 W
8.5
Full review
Intel · Core i5
Intel Core i5-9400
6C / 6T4.1 GHz65 W
8
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Desktop
Desktop
Segment
Mainstream Desktop
Mainstream Desktop
Generation
Core i5 (Coffee Lake)
Core i5 (Coffee Lake Refresh)
Launched
2017
2018
Status
End-of-life
End-of-life
Codename
Coffee Lake
Coffee Lake
Series
Core i5
Core i5
Family
8th Generation (Coffee Lake)
9th Generation (Coffee Lake Refresh)
Predecessor
Intel Core i5-7500
Intel Core i5-8400
Successor
Intel Core i5-9400
Intel Core i5-10400

Specifications Compared

Cores & Clocks
Cores
6
6
Threads
6
6
Base Clock
2.8 GHz
2.9 GHz
Boost Clock
4 GHz
4.1 GHz
Cache & Power
L3 Cache
9 MB
9 MB
TDP
65 W
65 W
Architecture
Architecture
Coffee Lake
Coffee Lake
Process Node
14 nm
14 nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
DDR4-2666
DDR4-2666
Memory Channels
Dual (2)
Dual (2)
Max Memory
64 GB
128 GB
Platform & I/O
Socket
Intel Socket 1151
Intel Socket 1151
PCIe Version
PCIe 3.0
PCIe 3.0
PCIe Lanes
16
16
Integrated GPU
Yes
Yes
Unlocked
No
No

Performance Compared

Productivity

Intel Core i5-840080

Handles office tasks and moderate programming workloads efficiently.

Intel Core i5-940080

Handles office tasks and moderate programming workloads efficiently.

Gaming

Intel Core i5-840078

Capable of smooth 1080p gaming when paired with a mid-range discrete GPU.

Intel Core i5-940078

Capable of smooth 1080p gaming when paired with a mid-range discrete GPU.

Virtualization

Intel Core i5-840065

Good for basic VMs, but 6 threads limit heavy parallel virtualization.

Intel Core i5-940065

Good for basic VMs, but 6 threads limit heavy parallel virtualization.

Efficiency

Intel Core i5-840085

Balanced performance within a standard 65W power envelope.

Intel Core i5-940085

Balanced performance within a standard 65W power envelope.

Specialized Performance

AI / ML

Intel Core i5-8400Limited
  • No AI-specific hardware
  • CPU inference is slow due to lack of threads
Intel Core i5-9400Limited
  • No AI-specific hardware
  • CPU inference is slow due to lack of threads

Content Creation

Intel Core i5-8400Moderate
1080p Video EditingBasic Photo ManipulationAudio Production
Intel Core i5-9400Moderate
1080p Video EditingBasic Photo ManipulationAudio Production

Gaming

Intel Core i5-8400Very Good
  • Excellent for budget gaming builds
  • Handles eSports titles flawlessly
  • May bottleneck high-end modern GPUs at 1080p
Intel Core i5-9400Good
  • Excellent for budget gaming builds
  • Handles eSports titles flawlessly
  • May bottleneck high-end modern GPUs at 1080p

Industry Impact

Gaming
High
High
Workstations
Moderate
Moderate
Content Creation
Moderate
Moderate
Virtualization
Moderate
Moderate

Best CPU by Use Case

1080p Gaming
Very Good
Very Good
Office Productivity
Excellent
Excellent
Web Development
Very Good
Very Good
Media Consumption
Excellent
Excellent
Video Conferencing
Excellent
Excellent

Target Audience

Gamers
Targeted
Targeted
Content Creators
Developers
Targeted
Targeted
Workstation Users
Streamers
Office / Productivity
Targeted
Targeted
Students
Targeted
Targeted

Strengths & Weaknesses

Intel Core i5-8400

Pros

  • Disruptive price-to-performance ratio
  • 6 physical cores for modern gaming
  • Includes integrated UHD Graphics 630
  • Standard 65W TDP is easy to cool
  • Wide compatibility with 300-series motherboards

Cons

  • No Hyper-Threading (only 6 threads)
  • Locked multiplier prevents overclocking
  • End-of-life platform (LGA 1151)
  • Officially limited to DDR4-2666
  • Not supported by Windows 11 officially
Intel Core i5-9400

Pros

  • Excellent price-to-performance ratio historically
  • Strong single-core speeds for gaming
  • Includes integrated UHD Graphics 630
  • Standard 65W TDP is easy to cool
  • Wide compatibility with 300-series motherboards

Cons

  • No Hyper-Threading (only 6 threads)
  • Locked multiplier prevents overclocking
  • End-of-life platform (LGA 1151)
  • Officially limited to DDR4-2666
  • Not supported by Windows 11 officially

Competitors & Alternatives

Intel Core i5-8400

Intel Core i5-9400

Our Verdict on Each

A legendary value CPU that forced the market to adopt 6 cores as the standard. Excellent for budget gaming, though lacking Hyper-Threading.

Best for: Upgrading an older LGA 1151 system on a budget, or building an office/HTPC machine.

Read the full review

A highly popular, cost-effective 6-core processor that delivers excellent value for mainstream users, though lacking Hyper-Threading limits its heavy multitasking ceiling.

Best for: Upgrading an older LGA 1151 system on a budget, or building an office/HTPC machine.

Read the full review

Frequently Asked Questions

Which is better, Intel Core i5-8400 or Intel Core i5-9400?

Based on our editorial ratings, the Intel Core i5-8400 comes out ahead with a score of 8.5/10. That said, the best choice depends on your workload — check the spec and performance breakdown above for gaming, productivity and efficiency differences.

Do Intel Core i5-8400 and Intel Core i5-9400 use the same socket?

Yes — all of these CPUs use the Intel Socket 1151 socket, so they share compatible motherboards.