CPU Comparison
Core i7-7800X vs Core i7-7820X
A side-by-side comparison of specs, performance and value. The Intel Core i7-7800X is a high-end desktop (HEDT) processor launched in June 2017 as part of the Skylake-X family. Designed for the LGA 2066 socket, this 14nm CPU features 6 cores and 12 threads, providing a substantial multi-threaded upgrade over mainstream quad-core parts of the era. Operating at a base clock of 3.5 GHz and boosting up to 4.0 GHz, it balances frequency with core density for workstation workloads. With a 140W TDP, it requires robust cooling and a capable motherboard. The processor features a unique cache hierarchy with 8.25MB of L3 cache and 1MB of dedicated L2 cache per core. It supports quad-channel DDR4-2400 memory, offering massive memory bandwidth, and includes 28 PCIe 3.0 lanes for extensive expansion capabilities. Lacking integrated graphics, it targets creators and enthusiasts who rely on discrete GPUs. The i7-7800X brought true HEDT features to a more accessible price point, though it faced fierce competition from AMD's Ryzen Threadripper.
The Bottom Line
Overview & Launch
Specifications Compared
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
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- Outdated 14nm process
Pros
- Strong 8-core multi-threaded performance
- Turbo Boost Max 3.0 for high single-core bursts
- Quad-channel memory support
- AVX-512 support
Cons
- High 140W TDP
- Runs very hot (uses thermal paste)
- Lacks integrated graphics
- Expensive X299 platform
Competitors & Alternatives
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
Core i7-7820X
- AMD Ryzen Threadripper 1900XRival
High-End Desktop
- Compare head-to-headIntel Core i9-7900XRival
High-End Desktop
- AMD Ryzen 7 1800XRival
High-End Desktop
- Compare head-to-headIntel Core i7-6900KRival
High-End Desktop
- Compare head-to-headIntel Core i7-7800XRival
High-End Desktop
- AMD Ryzen Threadripper 1920XAlt
12 cores and 64 PCIe lanes for similar money.
Better gaming performance on mainstream platform.
Compare head-to-head- AMD Ryzen 9 3900XAlt
12 cores, much more efficient and modern.
Our Verdict on Each
A 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 reviewAn excellent 8-core HEDT processor for 2017, offering a great balance of frequency and core count, though it suffers from high thermals.
Best for: Used budget workstation build
Read the full reviewFrequently Asked Questions
Which is better, Core i7-7800X or Core i7-7820X?
Based on our editorial ratings, the Core i7-7820X 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.
Do Core i7-7800X and Core i7-7820X use the same socket?
Yes — all of these CPUs use the LGA 2066 socket, so they share compatible motherboards.
Which has more cores?
The Core i7-7820X has the most cores. Core counts: Core i7-7800X (6 cores), Core i7-7820X (8 cores).