CPU Comparison

Intel Core i7-5820K vs Intel Core i7-6850K

A side-by-side comparison of specs, performance and value. The Intel Core i7-5820K is a high-end desktop (HEDT) processor built on the Haswell-E architecture. Designed for enthusiasts and professionals, it features six cores and twelve threads, offering a significant multi-threaded performance leap over mainstream quad-core CPUs of its era. Operating at a base frequency of 3.3 GHz and boosting up to 3.6 GHz, it delivers robust computing power for demanding applications. Unlike mainstream chips, it utilizes the LGA 2011-v3 socket and the X99 chipset, supporting quad-channel DDR4 memory for massive memory bandwidth. With 28 PCIe 3.0 lanes, it provides extensive expansion capabilities for multi-GPU setups and high-speed storage arrays. The 140-watt TDP reflects its workstation-class design. While it lacks integrated graphics, requiring a discrete GPU, the 5820K excels in parallel processing tasks like video editing, 3D rendering, and virtualization, making it a powerhouse for creators who need more than standard desktop platforms offer.

Top pick
Intel · Core i7
Intel Core i7-5820K
6C / 12T3.6 GHz140 W
8
Full review
Intel · Core i7
Intel Core i7-6850K
6C / 12T3.8 GHz140 W
7.4
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Desktop
High-End Desktop
Segment
High-End Desktop
Generation
Core i7 (Haswell-E)
6th Gen X-Series (Broadwell-E)
Launched
2014
2016
Status
End-of-life
Discontinued
Codename
Haswell-E
Broadwell-E
Series
Core i7
Core i7
Family
5th Generation
Broadwell-E (Core i7)
Predecessor
Intel Core i7-4930K
Intel Core i7-5820K
Successor
Intel Core i7-6800K
Platform discontinued; Skylake-X and Cascade Lake-X followed on LGA2066

Specifications Compared

Cores & Clocks
Cores
6
6
Threads
12
12
Base Clock
3.3 GHz
3.6 GHz
Boost Clock
3.6 GHz
3.8 GHz
Cache & Power
L3 Cache
15 MB
15 MB
TDP
140 W
140 W
Architecture
Architecture
Haswell-E
Broadwell-E
Process Node
22nm
14 nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
2133 MT/s
DDR4-2400/2133
Memory Channels
Quad (4)
Quad (4)
Max Memory
128 GB
128 GB
Platform & I/O
Socket
Intel Socket 2011-3
LGA2011-v3
PCIe Version
Gen 3
3.0
PCIe Lanes
28
40
Integrated GPU
None
None
Unlocked
Yes
Yes

Performance Compared

Productivity

Intel Core i7-5820K72

6 cores handle rendering well, but lack the speed of modern architectures.

Intel Core i7-6850KBest80

Strong multi-core performance for its generation, adequate for many creator workloads if overclocked.

Gaming

Intel Core i7-5820K60

Good for gaming, but single-core speed lags behind modern CPUs.

Intel Core i7-6850KBest75

Handles modern games paired with a strong GPU, but newer mainstream CPUs offer higher frame rates and better efficiency.

Virtualization

Intel Core i7-5820K78

Quad-channel memory and 12 threads make it great for VMs.

Intel Core i7-6850KBest84

40 PCIe lanes and VT-x/VT-d support make it practical for lab and VM setups.

Efficiency

Intel Core i7-5820K35

140W TDP on 22nm is power-hungry by modern standards.

Intel Core i7-6850KBest58

High 140 W TDP and 14 nm process result in notable power draw versus modern alternatives.

Specialized Performance

AI / ML

Intel Core i7-5820KLimited
  • No AI hardware
  • CPU inference is moderate due to core count
Intel Core i7-6850KLimited
  • No dedicated AI acceleration hardware; runs only CPU-based inference.
  • AVX2 support helps with some vectorized compute workloads.

Content Creation

Intel Core i7-5820KVery Good
Premiere ProBlenderAutoCADDaVinci Resolve
Intel Core i7-6850KVery Good
Adobe Premiere ProDaVinci ResolveBlenderCinema 4DAfter Effects

Gaming

Intel Core i7-5820KGood
  • Can handle modern games with a discrete GPU
  • Lower single-core speed limits high-refresh gaming
  • Great for multi-tasking while gaming
Intel Core i7-6850KGood
  • Base and turbo clocks are sufficient for high-refresh gaming with a capable GPU.
  • PCIe 3.0 x16 remains viable for current graphics cards.
  • Gaming performance is limited by older IPC and DDR4-2400 compared to newer platforms.

Industry Impact

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

Best CPU by Use Case

4K Video Editing
Very Good
Very Good
3D Rendering
Very Good
Very Good
Virtual Machines
Excellent
1440p Gaming
Good
Compilation
Excellent
Multi-GPU configurations
Excellent
Virtualization
Very Good
Gaming at 1440p+
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

  • 6 cores / 12 threads
  • 28 PCIe lanes
  • Quad-channel DDR4 memory
  • Unlocked for overclocking

Cons

  • High 140W TDP
  • Older 22nm process
  • Only 28 PCIe lanes
  • Lacks integrated graphics
Intel Core i7-6850K

Pros

  • Six cores and 12 threads
  • 40 PCIe 3.0 lanes
  • Quad-channel DDR4-2400
  • Unlocked multiplier with Turbo Boost Max 3.0
  • Strong I/O expansion for multi-GPU/NVMe
  • VT-x and VT-d support for virtualization

Cons

  • No integrated graphics
  • High 140 W TDP
  • Discontinued platform with limited future upgrade path
  • Lower memory speed limit (DDR4-2400)
  • Not on official Windows 11 supported processor list

Competitors & Alternatives

Intel Core i7-5820K

  • AMD Ryzen 7 1700X

    High-End Desktop

    Rival
  • Intel Core i7-4930K

    High-End Desktop

    Rival
  • AMD FX-8350

    Desktop

    Rival
  • Intel Core i7-6800K

    High-End Desktop

    Rival
    Compare head-to-head
  • Intel Core i7-5930K

    High-End Desktop

    Rival
    Compare head-to-head
  • AMD Ryzen 5 5600X
    Alt

    Vastly superior single-core speed and efficiency.

  • Intel Core i5-12400F
    Alt

    Modern alternative that beats it in almost everything.

  • AMD Ryzen 7 5700X
    Alt

    8 cores, better IPC, lower power.

Intel Core i7-6850K

Our Verdict on Each

A solid entry point into the HEDT market, offering 6 cores and DDR4 support, though aging rapidly compared to modern alternatives.

Best for: Upgrading an existing X99 system for more cores.

Read the full review

A capable HEDT chip with strong multi-threaded performance and plentiful I/O for its time, but high power draw and a discontinued platform make it relevant mainly as a budget used upgrade.

Best for: Upgrade for existing X99/LGA2011-v3 systems seeking more cores or PCIe lanes at low cost.

Read the full review

Frequently Asked Questions

Which is better, Intel Core i7-5820K or Intel Core i7-6850K?

Based on our editorial ratings, the Intel Core i7-5820K comes out ahead with a score of 8/10. 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 i7-5820K or Intel Core i7-6850K?

For gaming, the Intel Core i7-6850K leads with a gaming performance score of 75/100 among Intel Core i7-5820K and Intel Core i7-6850K.

Do Intel Core i7-5820K and Intel Core i7-6850K use the same socket?

No. They use different sockets (Intel Core i7-5820K: Intel Socket 2011-3, Intel Core i7-6850K: LGA2011-v3), so each needs a compatible motherboard.

Which is faster in multi-core benchmarks?

The Intel Core i7-5820K posts the highest multi-core benchmark score. Multi-core results: Intel Core i7-5820K (11,000). Benchmark figures are approximate and workload-dependent.