CPU Comparison

Intel Core i5-6600K vs Core i5-7640X

A side-by-side comparison of specs, performance and value. The Intel Core i5-6600K is an unlocked 4-core, 4-thread Skylake desktop processor designed specifically for enthusiasts and gamers who wanted robust overclocking capabilities on the Z170 platform.

Top pick
Intel · Core i5
Intel Core i5-6600K
4C / 4T3.9 GHz91 W
7.5
Full review
Intel · Core i5
Core i5-7640X
4C / 4T4.3 GHz112 W
6.5
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Desktop
Desktop
Segment
Mainstream Enthusiast Desktop
High-End Desktop
Generation
6th Gen (Skylake)
7th Gen (Kaby Lake-X)
Launched
2015
2017
Status
End-of-life
End-of-life
Codename
Skylake
Kaby Lake-X
Series
Core i5
Core i5
Family
6th Gen (Skylake)
X-Series
Predecessor
Intel Core i5-4690K
Intel Core i5-6600K
Successor
Intel Core i5-7600K
Intel Core i5-9600K

Specifications Compared

Cores & Clocks
Cores
4
4
Threads
4
4
Base Clock
3.5 GHz
3.9 GHz
Boost Clock
3.9 GHz
4.3 GHz
Cache & Power
L3 Cache
6 MB
6 MB
TDP
91 W
112 W
Architecture
Architecture
Skylake
Kaby Lake-X
Process Node
14nm
14nm
Memory
Memory Type
DDR3, DDR4
DDR4
Memory Speed
DDR4-2133
DDR4-2666
Memory Channels
Dual (2)
Dual (2)
Max Memory
64 GB
64 GB
Platform & I/O
Socket
LGA 1151
LGA 2066
PCIe Version
PCIe 3.0
PCIe 3.0
PCIe Lanes
16
16
Integrated GPU
Yes
None
Unlocked
Yes
Yes

Performance Compared

Productivity

Intel Core i5-6600K45

Lacks hyper-threading, making it slow for modern multi-threaded productivity workloads.

Core i5-7640X

Adequate for basic office tasks and light workloads, but falls behind in heavily multi-threaded applications.

Gaming

Intel Core i5-6600K65

Bottlenecks modern GPUs in CPU-heavy titles due to 4 threads, but adequate for older or eSports games.

Core i5-7640X

Performs well in older or less demanding games due to high IPC and clock speeds, but bottlenecks modern titles due to 4-core/4-thread limitations.

Virtualization

Intel Core i5-6600K35

Very limited for VMs due to low thread count and lack of ECC support.

Core i5-7640X

Limited utility for virtualization due to the lack of Hyper-Threading and low core count.

Efficiency

Intel Core i5-6600K55

14nm Skylake was efficient for its time, but 91W TDP is high by today's standards for 4 cores.

Core i5-7640X

14nm process and 112W TDP for a 4-core chip result in poor efficiency compared to mainstream alternatives.

Specialized Performance

AI / ML

Intel Core i5-6600KVery Poor
  • No AI acceleration hardware
  • 4 threads severely limit local inference capabilities
Core i5-7640XPoor
  • No dedicated AI hardware
  • Low core count limits CPU-based inference

Content Creation

Intel Core i5-6600KPoor
Basic Photo EditingLight 1080p Video Editing
Core i5-7640XFair
Basic Photo EditingAudio Production

Gaming

Intel Core i5-6600KFair
  • Struggles in modern AAA games that use 6+ threads
  • Great for eSports titles like CS:GO and Valorant
  • Overclocking helps maintain minimum frame rates
Core i5-7640XGood
  • High clock speeds benefit high-refresh-rate gaming
  • 4 cores struggle with modern CPU-intensive titles
  • Requires a dedicated GPU

Industry Impact

Gaming
Moderate
Low
Workstations
Low
Low
Content Creation
Low
Low
Virtualization
Low
Low

Best CPU by Use Case

1080p eSports Gaming
Good
Overclocking
Excellent
Everyday Computing
Excellent
Light Content Creation
Fair
Programming
Very Good
1080p Gaming
Very Good
Competitive eSports
Excellent
Heavy Multitasking
Poor
Video Editing
Fair

Target Audience

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

Strengths & Weaknesses

Intel Core i5-6600K

Pros

  • Unlocked multiplier for easy overclocking
  • Solid IPC for its generation
  • Integrated HD 530 graphics for troubleshooting
  • Supports DDR4 memory
  • Great overclocking headroom (often hit 4.5-4.7GHz)

Cons

  • Only 4 threads without Hyper-Threading
  • 91W TDP is relatively high for a 4-core processor
  • End-of-life platform with no upgrade path
  • Struggles with modern gaming workloads
  • Requires discrete GPU for any serious gaming
  • Does not include a stock cooler
Core i5-7640X

Pros

  • Unlocked multiplier for overclocking
  • High 4.3 GHz turbo frequency
  • Access to X299 chipset features
  • Strong single-core performance for its era

Cons

  • Only 4 cores and 4 threads
  • Limited to dual-channel memory
  • Only 16 PCIe lanes
  • Lacks integrated graphics
  • Poor price-to-performance ratio at launch

Competitors & Alternatives

Intel Core i5-6600K

Core i5-7640X

Our Verdict on Each

A legendary overclocker in its day, the i5-6600K brought DDR4 and PCIe 3.0 to the mainstream, though its 4-thread limitation shows its age in modern titles.

Best for: The Intel Core i5-6600K is only recommended today if you already own an LGA 1151 motherboard and DDR4 memory, and you are looking for a drop-in upgrade or replacement for a broken Pentium or i3 on a strict zero-budget. It can still handle everyday web browsing, office tasks, and esports titles like CS:GO or Valorant reasonably well. If you are building a system from scratch, there is absolutely no reason to purchase this processor new. Modern entry-level CPUs like the i3-12100F or Ryzen 5 5600 dramatically outperform it in every metric while offering a viable upgrade path. The used market is the only place this chip makes sense, and even then, you should avoid paying more than a fraction of its original launch price due to its heavily constrained multi-threading capability and dead-end platform status.

Read the full review
Core i5-7640XSituational

A peculiar HEDT chip with high clock speeds but limited PCIe lanes and no Hyper-Threading, making it a niche product for overclockers rather than a true workstation CPU.

Best for: Hobbyist overclocking on a used X299 motherboard

Read the full review

Frequently Asked Questions

Which is better, Intel Core i5-6600K or Core i5-7640X?

Based on our editorial ratings, the Intel Core i5-6600K comes out ahead with a score of 7.5/10. That said, the best choice depends on your workload — check the spec and performance breakdown above for gaming, productivity and efficiency differences.

Which is faster for gaming, Intel Core i5-6600K or Core i5-7640X?

For gaming, the Intel Core i5-6600K leads with a gaming performance score of 65/100 among Intel Core i5-6600K and Core i5-7640X.

Which uses less power?

The Intel Core i5-6600K has the lowest rated TDP. Power draw across these chips: Intel Core i5-6600K (91 W), Core i5-7640X (112 W).

Do Intel Core i5-6600K and Core i5-7640X use the same socket?

No. They use different sockets (Intel Core i5-6600K: LGA 1151, Core i5-7640X: LGA 2066), so each needs a compatible motherboard.

Which is faster in multi-core benchmarks?

The Intel Core i5-6600K posts the highest multi-core benchmark score. Multi-core results: Intel Core i5-6600K (5,800). Benchmark figures are approximate and workload-dependent.