CPU Comparison

Intel Core i7-5820K vs Intel Core i7-7820X

A side-by-side comparison of specs, performance and value. The Intel Core i7-5820K is a six-core enthusiast processor that introduced the X99 platform and DDR4 memory to the high-end desktop market, offering a balance of multi-threaded performance and affordability.

Intel · Core i7
Intel Core i7-5820K
6C / 12T3.6 GHz140 W
7.5
Full review
Intel · Core i7
Intel Core i7-7820X
8C / 16T4.5 GHz140 W
7.5
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
High-End Desktop (HEDT)
High-End Desktop (HEDT)
Generation
4th Generation X-Series
7th Gen X-Series (Skylake-X)
Launched
2014
2017
Status
Discontinued
Discontinued
Codename
Haswell-E
Skylake-X
Series
Core i7
Core i7
Family
Haswell-E (Core i7)
X-Series 7th Gen (Core i7)
Predecessor
Intel Core i7-4930K
Intel Core i7-6900K
Successor
Intel Core i7-6850K
Platform discontinued; refreshed X299 and later Core X-series succeeded this lineup

Specifications Compared

Cores & Clocks
Cores
6
8
Threads
12
16
Base Clock
3.3 GHz
3.6 GHz
Boost Clock
3.6 GHz
4.5 GHz
Cache & Power
L3 Cache
15 MB
11 MB
TDP
140 W
140 W
Architecture
Architecture
Haswell-E
Skylake-X
Process Node
22 nm
14 nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
DDR4-2133
DDR4-2666
Memory Channels
Quad (4)
Quad (4)
Max Memory
64 GB
128 GB
Platform & I/O
Socket
FCLGA2011-3 (LGA2011-v3)
LGA2066
PCIe Version
3.0
3.0
PCIe Lanes
28
28
Integrated GPU
None
None
Unlocked
Yes
Yes

Performance Compared

Productivity

Intel Core i7-5820K75

Solid performance for older software and moderate rendering tasks, but falls behind modern 6-core CPUs in IPC and clock speed.

Intel Core i7-7820XBest88

Strong multi-threaded throughput in CINEBENCH, HandBrake, and similar workloads at launch; still competent for many content creation tasks compared to modern mainstream parts.

Gaming

Intel Core i7-5820K65

Playable in modern esports and AAA titles when paired with a strong GPU, but likely to bottleneck top-tier cards in CPU-intensive scenarios.

Intel Core i7-7820XBest78

Delivers high frame rates in 2017-era titles and remains adequate for modern gaming, but newer gaming-focused CPUs with higher clocks and improved IPC pull ahead.

Virtualization

Intel Core i7-5820K85

Excellent value for home labs due to high core count, VT-d support, and PCIe lane availability for multiple NICs or storage controllers.

Intel Core i7-7820X85

PCIe and memory bandwidth are helpful for multiple VMs, but core count is moderate for modern heavy virtualization needs.

Efficiency

Intel Core i7-5820K40

High power consumption (140W TDP) and heat output compared to 14nm, 10nm, or 7nm counterparts.

Intel Core i7-7820XBest60

High 140 W TDP and 14 nm process lead to greater power consumption versus newer 7 nm and smaller nodes.

Specialized Performance

AI / ML

Intel Core i7-5820KPoor
  • No dedicated AI or matrix acceleration hardware.
  • AVX2 support offers some vector compute capability.
Intel Core i7-7820XLimited
  • No dedicated AI acceleration hardware
  • AVX-512 can help certain CPU-bound inference tasks
  • Most modern AI workloads are better served by GPUs

Content Creation

Intel Core i7-5820KGood
Adobe Premiere ProAdobe PhotoshopBlenderHandbrakeVisual Studio
Intel Core i7-7820XVery Good
Adobe Premiere ProDaVinci ResolveBlenderCinema 4DAfter Effects

Gaming

Intel Core i7-5820KAverage
  • Requires discrete graphics; no integrated GPU.
  • PCIe 3.0 lanes limit full potential of modern RTX 40-series GPUs.
  • Boost clocks are modest by modern standards.
Intel Core i7-7820XGood
  • Capable of high-refresh gaming with a strong GPU
  • Single-core boost reaches up to 4.5 GHz on favored cores
  • Modern CPUs offer better gaming efficiency and higher IPC

Industry Impact

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

Best CPU by Use Case

1080p Gaming
Good
1080p/1440p Streaming
Good
Video Editing (1080p/4K)
Good
3D Rendering
Average
Very Good
Home Server / Virtualization
Very Good
4K Video Editing
Very Good
Software Compilation
Very Good
Virtualization
Good
Gaming
Good

Target Audience

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

Strengths & Weaknesses

Intel Core i7-5820K

Pros

  • Relatively low entry cost for a used HEDT platform
  • Quad-channel DDR4 memory support
  • 28 PCIe lanes allow for multiple expansion cards
  • Unlocked for overclocking
  • Strong multi-core performance for its era

Cons

  • High power draw and heat output
  • No integrated graphics
  • Limited to 28 PCIe lanes (fewer than 5930K/5960X)
  • Requires expensive X99 motherboards and DDR4 RAM
  • Older architecture lacks modern instruction sets like AVX-512
Intel Core i7-7820X

Pros

  • 8 cores and 16 threads for multi-threaded workloads
  • Quad-channel DDR4 memory increases bandwidth
  • 28 PCIe 3.0 lanes plus chipset lanes for expansion
  • Turbo Boost Max 3.0 for higher single-core boosts
  • AVX-512 support for optimized workloads
  • Unlocked multiplier for overclocking

Cons

  • High 140 W TDP and power consumption
  • No integrated graphics
  • Only 28 CPU PCIe lanes, limiting multi-GPU configurations
  • Discontinued platform with limited future upgrades
  • Older 14 nm process versus modern smaller nodes

Competitors & Alternatives

Intel Core i7-5820K

Intel Core i7-7820X

  • AMD Ryzen 7 1800X

    Creator/Gaming

    Rival
  • AMD Ryzen 7 1700X

    Creator/Gaming

    Rival
  • AMD Ryzen Threadripper 1920X

    Workstation

    Rival
  • AMD Ryzen Threadripper 1950X

    Workstation

    Rival
  • Compare head-to-head
  • More cores, higher efficiency, and DDR5 on a modern mainstream platform.

    Compare head-to-head
  • AMD Ryzen 9 7900
    Alt

    Strong multi-threaded performance with excellent efficiency.

  • AMD Ryzen 9 5900X
    Alt

    12-core AM4 option with strong gaming and creator performance.

  • High-performance mainstream platform with good upgrade path.

    Compare head-to-head
  • AMD Ryzen Threadripper 2950X (used)
    Alt

    Higher core and lane count for workstation-class workloads.

Our Verdict on Each

The i7-5820K was a groundbreaking value proposition in 2014, bringing DDR4 and quad-channel memory to a lower price point. Today, it remains viable only for budget builds, handicapped by high power consumption and limited PCIe lanes compared to modern standards.

Best for: Building a budget-friendly used workstation for virtualization or light content creation.

Read the full review

A competent eight-core HEDT chip with strong multi-threaded performance and platform expansion, though high power draw and limited PCIe lanes compared to higher-tier X299 CPUs make it a niche choice today.

Best for: Used-market upgrade for an existing X299 build with quad-channel DDR4 and a need for more cores than mainstream.

Read the full review

Frequently Asked Questions

Which is faster for gaming, Intel Core i7-5820K or Intel Core i7-7820X?

For gaming, the Intel Core i7-7820X leads with a gaming performance score of 78/100 among Intel Core i7-5820K and Intel Core i7-7820X.

Do Intel Core i7-5820K and Intel Core i7-7820X use the same socket?

No. They use different sockets (Intel Core i7-5820K: FCLGA2011-3 (LGA2011-v3), Intel Core i7-7820X: LGA2066), so each needs a compatible motherboard.

Which has more cores?

The Intel Core i7-7820X has the most cores. Core counts: Intel Core i7-5820K (6 cores), Intel Core i7-7820X (8 cores).