CPU Comparison

Intel Core i7-5820K vs Intel Core i9-10900K

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 X-Series
Intel Core i7-5820K
6C / 12T3.6 GHz140 W
7.5
Full review
Top pick
Intel · Core i9
Intel Core i9-10900K
10C / 20T5.3 GHz125 W
8.2
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
High-End Desktop (HEDT)
Desktop
Segment
High-End Desktop
Generation
4th Generation X-Series
10th Gen Core (Comet Lake-S)
Launched
2014
2020
Status
Discontinued
End-of-life
Codename
Haswell-E
Comet Lake-S
Series
Core X-Series
Core i9
Family
Haswell-E
10th Generation Core
Predecessor
Intel Core i7-4930K
Intel Core i9-9900K
Successor
Intel Core i7-6850K
Intel Core i9-11900K

Specifications Compared

Cores & Clocks
Cores
6
10
Threads
12
20
Base Clock
3.3 GHz
3.7 GHz
Boost Clock
3.6 GHz
5.3 GHz
Cache & Power
L3 Cache
15 MB
20 MB
TDP
140 W
125 W
Architecture
Architecture
Haswell-E
Comet Lake-S
Process Node
22 nm
14nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
DDR4-2133
DDR4-2933
Memory Channels
Quad (4)
Dual (2)
Max Memory
64 GB
128 GB
Platform & I/O
Socket
FCLGA2011-3 (LGA2011-v3)
LGA 1200
PCIe Version
3.0
PCIe 3.0
PCIe Lanes
28
16
Integrated GPU
None
Yes
Unlocked
Yes
Yes

Performance Compared

Productivity

Intel Core i7-5820K75
Intel Core i9-10900KBest82

Gaming

Intel Core i7-5820K65
Intel Core i9-10900KBest88

Virtualization

Intel Core i7-5820KBest85
Intel Core i9-10900K78

Efficiency

Intel Core i7-5820K40
Intel Core i9-10900KBest45

Specialized Performance

AI / ML

Intel Core i7-5820KPoor
  • No dedicated AI or matrix acceleration hardware.
  • AVX2 support offers some vector compute capability.
Intel Core i9-10900KLimited
  • No dedicated AI or neural processing hardware
  • AVX-512 is not supported on Comet Lake-S
  • CPU-based inference works but is far slower than dedicated accelerators or newer architectures with AI extensions
  • Suitable only for lightweight local AI tasks or experimentation

Content Creation

Intel Core i7-5820KGood
Adobe Premiere ProAdobe PhotoshopBlenderHandbrakeVisual Studio
Intel Core i9-10900KGood
Adobe Premiere ProAdobe After EffectsDaVinci ResolveBlender (CPU)HandBrakeOBS Studio

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 i9-10900KExcellent
  • 5.3 GHz boost provides outstanding single-threaded gaming performance
  • Consistently achieves high frame rates at 1080p with a powerful GPU
  • At 1440p and 4K, GPU becomes the bottleneck, narrowing the gap with newer CPUs
  • All-core gaming loads typically run at 4.7–4.9 GHz with adequate cooling
  • Fast memory tuning (DDR4-4000+) on Z490/Z590 can further improve frame pacing

Industry Impact

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

Best CPU by Use Case

1080p Gaming
Good
1080p/1440p Streaming
Good
Video Editing (1080p/4K)
Good
3D Rendering
Average
Good
Home Server / Virtualization
Very Good
High-Refresh-Rate Gaming (144Hz+)
Excellent
Game Streaming (Single PC)
Very Good
Video Editing (4K)
Good
Software Compilation
Very Good
Office Productivity
Overkill

Target Audience

Gamers
Targeted
Targeted
Content Creators
Targeted
Targeted
Developers
Targeted
Targeted
Workstation Users
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 i9-10900K

Pros

  • 5.3 GHz max boost — outstanding single-threaded performance
  • 10 cores and 20 threads provide solid multi-threaded capability
  • Excellent 1080p gaming performance with high frame rates
  • Unlocked multiplier for enthusiast overclocking
  • LGA 1200 supports both 400-series and 500-series chipsets
  • Mature platform with stable drivers and broad motherboard selection
  • UHD 630 iGPU provides display output without a discrete GPU for troubleshooting

Cons

  • High power consumption — regularly exceeds 200W under sustained load
  • Runs hot — demands premium cooling (280mm+ AIO recommended)
  • 14nm process is outdated and inefficient compared to modern alternatives
  • No PCIe 4.0 support — limits NVMe SSD and GPU bandwidth ceiling
  • No DDR5 support — locked to DDR4 platform
  • Successor i9-11900K actually reduced core count to 8 due to Rocket Lake constraints
  • No AVX-512 support unlike the later Rocket Lake generation

Competitors & Alternatives

Intel Core i7-5820K

  • AMD Ryzen 5 1600

    Mainstream

    Rival
  • AMD Ryzen 7 1700

    Creator

    Rival
  • Intel Core i7-4790K

    Gaming

    Rival
  • AMD FX-9590

    Enthusiast

    Rival
  • Rival
    Compare head-to-head
  • If you need the full 40 PCIe lanes for tri-SI or heavy storage arrays.

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

    A modern, significantly faster and more efficient gaming CPU.

  • Intel Core i5-12600K
    Alt

    Modern platform with PCIe 5.0 and DDR5 support.

  • AMD Ryzen 9 5900X
    Alt

    Massive multi-core performance jump for content creation.

  • More cores and higher frequency on a still-recent mainstream platform.

    Compare head-to-head

Intel Core i9-10900K

  • AMD Ryzen 9 3900X

    High-End Desktop

    Rival
  • AMD Ryzen 7 5800X

    High-End Desktop

    Rival
  • AMD Ryzen 9 5900X

    High-End Desktop

    Rival
  • Intel Core i9-11900K

    High-End Desktop

    Rival
    Compare head-to-head
  • AMD Ryzen 7 5700X

    Mainstream Desktop

    Rival
  • Intel Core i5-13600K
    Alt

    Newer hybrid architecture delivers better multi-threaded and gaming performance at lower power consumption and similar price points on the used market.

  • AMD Ryzen 7 7700X
    Alt

    Offers competitive gaming performance with dramatically better power efficiency on the AM5 platform with DDR5 and PCIe 5.0 support.

  • Intel Core i7-12700K
    Alt

    Alder Lake's 12-core hybrid design outperforms the i9-10900K in virtually every metric while consuming less power under load.

  • Intel Core i9-9900K
    Alt

    If multi-threaded workloads are not critical, the 8-core predecessor runs cooler and is often available at a significant discount on the used market.

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

The i9-10900K was the ultimate 14nm Comet Lake flagship, pushing clock speeds to 5.3 GHz and delivering 10 cores for gaming and productivity. While it remains highly capable, its high power draw and lack of DDR5 or PCIe 4.0 make newer platforms more compelling for new builds.

Best for: Budget-conscious used-market builder who already owns an LGA 1200 motherboard and wants maximum cores without replacing the platform.

Read the full review

Frequently Asked Questions

Which is better, Intel Core i7-5820K or Intel Core i9-10900K?

Based on our editorial ratings, the Intel Core i9-10900K comes out ahead with a score of 8.2/10. 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 i9-10900K?

For gaming, the Intel Core i9-10900K leads with a gaming performance score of 88/100 among Intel Core i7-5820K and Intel Core i9-10900K.

Which uses less power?

The Intel Core i9-10900K has the lowest rated TDP. Power draw across these chips: Intel Core i7-5820K (140 W), Intel Core i9-10900K (125 W).

Do Intel Core i7-5820K and Intel Core i9-10900K use the same socket?

No. They use different sockets (Intel Core i7-5820K: FCLGA2011-3 (LGA2011-v3), Intel Core i9-10900K: LGA 1200), so each needs a compatible motherboard.

Which has more cores?

The Intel Core i9-10900K has the most cores. Core counts: Intel Core i7-5820K (6 cores), Intel Core i9-10900K (10 cores).

Which is faster in multi-core benchmarks?

The Intel Core i9-10900K posts the highest multi-core benchmark score. Multi-core results: Intel Core i9-10900K (10,500). Benchmark figures are approximate and workload-dependent.