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.

Intel · X-Series 7th Gen
Core i7-7800X
6C / 12T4 GHz140 W
7.5
Full review
Top pick
Intel · X-Series 7th Gen
Core i7-7820X
8C / 16T4.5 GHz140 W
8
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Desktop
Desktop
Segment
High-End Desktop
High-End Desktop
Generation
7th Gen X-Series
7th Gen X-Series
Launched
2017
2017
Status
End-of-life
End-of-life
Codename
Skylake-X
Skylake-X
Series
X-Series 7th Gen
X-Series 7th Gen
Family
Skylake-X
Skylake-X
Predecessor
Core i7-6800K
Core i7-6900K
Successor
Core i7-7820X
Core i9-9800X

Specifications Compared

Cores & Clocks
Cores
6
8
Threads
12
16
Base Clock
3.5 GHz
3.6 GHz
Boost Clock
4 GHz
4.5 GHz
Cache & Power
L3 Cache
8.25 MB
11 MB
TDP
140 W
140 W
Architecture
Architecture
Skylake-X
Skylake-X
Process Node
14nm
14nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
2400 MT/s
2666 MT/s
Memory Channels
Quad (4)
Quad (4)
Max Memory
128 GB
128 GB
Platform & I/O
Socket
LGA 2066
LGA 2066
PCIe Version
PCIe 3.0
PCIe 3.0
PCIe Lanes
28
28
Integrated GPU
None
None
Unlocked
Yes
Yes

Industry Impact

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

Best CPU by Use Case

3D Rendering
Very Good
Excellent
Video Editing
Very Good
4K Video Editing
Excellent

Target Audience

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

Strengths & Weaknesses

Core i7-7800X

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
Core i7-7820X

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

Core i7-7820X

Our Verdict on Each

Core i7-7800XSituational

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 review
Core i7-7820XSituational

An 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 review

Frequently 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).