CPU Comparison
Intel Core i7-5820K vs Core i7-7800X
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.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
6 cores handle rendering well, but lack the speed of modern architectures.
Gaming
Good for gaming, but single-core speed lags behind modern CPUs.
Virtualization
Quad-channel memory and 12 threads make it great for VMs.
Efficiency
140W TDP on 22nm is power-hungry by modern standards.
Specialized Performance
AI / ML
- No AI hardware
- CPU inference is moderate due to core count
No data
Content Creation
No data
Gaming
- Can handle modern games with a discrete GPU
- Lower single-core speed limits high-refresh gaming
- Great for multi-tasking while gaming
No data
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
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
Pros
- Quad-channel memory support
- 28 PCIe lanes for expansion
- Good multi-threaded performance
- AVX-512 support
Cons
- High 140W TDP
- Runs very hot under load
- Lacks integrated graphics
- Outdated 14nm process
Competitors & Alternatives
Intel Core i7-5820K
- AMD Ryzen 7 1700XRival
High-End Desktop
- Intel Core i7-4930KRival
High-End Desktop
- AMD FX-8350Rival
Desktop
- Compare head-to-headIntel Core i7-6800KRival
High-End Desktop
- Compare head-to-headIntel Core i7-5930KRival
High-End Desktop
- AMD Ryzen 5 5600XAlt
Vastly superior single-core speed and efficiency.
- Intel Core i5-12400FAlt
Modern alternative that beats it in almost everything.
- AMD Ryzen 7 5700XAlt
8 cores, better IPC, lower power.
Core i7-7800X
- AMD Ryzen 5 1600XRival
Mainstream Desktop
- Compare head-to-headIntel Core i7-7820XRival
High-End Desktop
- AMD Ryzen Threadripper 1900XRival
High-End Desktop
- Compare head-to-headIntel Core i7-6800KRival
High-End Desktop
- AMD Ryzen 7 1800XRival
High-End Desktop
Better gaming performance on a mainstream platform.
Compare head-to-head- AMD Ryzen 7 3700XAlt
Much more efficient and faster modern alternative.
True high-end HEDT performance with 10 cores.
Compare head-to-head
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 reviewA solid entry into Intel's HEDT platform, offering good multi-threaded performance and ample expansion, though it runs hot and is outdated by modern standards.
Best for: Cheap used workstation build
Read the full reviewFrequently Asked Questions
Which is better, Intel Core i7-5820K or Core i7-7800X?
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 Core i7-7800X?
For gaming, the Intel Core i7-5820K leads with a gaming performance score of 60/100 among Intel Core i7-5820K and Core i7-7800X.
Do Intel Core i7-5820K and Core i7-7800X use the same socket?
No. They use different sockets (Intel Core i7-5820K: Intel Socket 2011-3, Core i7-7800X: LGA 2066), 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), Core i7-7800X (0). Benchmark figures are approximate and workload-dependent.