CPU Comparison

Intel Core i7-7740X vs Intel Core i7-7820X

A side-by-side comparison of specs, performance and value. The Intel Core i7-7740X is a quad-core, eight-thread desktop processor from the Kaby Lake-X family, designed for the LGA2066 (X299) platform with 14 nm manufacturing, a base clock of 4.30 GHz, and a max turbo of 4.50 GHz.

Intel · Core i7
Intel Core i7-7740X
4C / 8T4.5 GHz112 W
7
Full review
Top pick
Intel · Core i7
Intel Core i7-7820X
8C / 16T4.5 GHz140 W
7.5
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Desktop
High-End Desktop (HEDT)
Generation
7th Gen X-Series (Kaby Lake-X)
7th Gen X-Series (Skylake-X)
Launched
2017
2017
Status
Discontinued
Discontinued
Codename
Kaby Lake-X
Skylake-X
Series
Core i7
Core i7
Family
X-Series 7th Gen (Core i7)
X-Series 7th Gen (Core i7)
Predecessor
Intel Core i7-7700K (mainstream)
Intel Core i7-6900K
Successor
Platform superseded by Skylake-X and later HEDT/enthusiast lines
Platform discontinued; refreshed X299 and later Core X-series succeeded this lineup

Specifications Compared

Cores & Clocks
Cores
4
8
Threads
8
16
Base Clock
4.3 GHz
3.6 GHz
Boost Clock
4.5 GHz
4.5 GHz
Cache & Power
L3 Cache
8 MB
11 MB
TDP
112 W
140 W
Architecture
Architecture
Kaby Lake-X
Skylake-X
Process Node
14 nm
14 nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
DDR4-2666
DDR4-2666
Memory Channels
Dual (2)
Quad (4)
Max Memory
64 GB
128 GB
Platform & I/O
Socket
LGA2066
LGA2066
PCIe Version
PCIe 3.0
3.0
PCIe Lanes
16
28
Integrated GPU
None
None
Unlocked
Yes
Yes

Performance Compared

Productivity

Intel Core i7-7740X68

Quad-core limits performance in heavily parallelized applications compared to higher core-count alternatives.

Intel Core i7-7820XBest88

Strong multi-threaded throughput in CINEBENCH, HandBrake, and similar workloads at launch; still competent for many content creation tasks compared to modern mainstream parts.

Gaming

Intel Core i7-7740X78

Paired with a strong discrete GPU, the high clocks enable smooth high-refresh gaming, though newer platforms offer better efficiency and future-proofing.

Intel Core i7-7820X78

Delivers high frame rates in 2017-era titles and remains adequate for modern gaming, but newer gaming-focused CPUs with higher clocks and improved IPC pull ahead.

Virtualization

Intel Core i7-7740X60

Adequate for light VM workloads, but limited core count and memory channels make it less suitable for heavy virtualization.

Intel Core i7-7820XBest85

PCIe and memory bandwidth are helpful for multiple VMs, but core count is moderate for modern heavy virtualization needs.

Efficiency

Intel Core i7-7740XBest62

112 W TDP for a quad-core results in higher power draw per core than many modern designs.

Intel Core i7-7820X60

High 140 W TDP and 14 nm process lead to greater power consumption versus newer 7 nm and smaller nodes.

Specialized Performance

AI / ML

Intel Core i7-7740XLimited
  • No dedicated AI acceleration hardware
  • Suited only for CPU-bound inference and older ML frameworks
Intel Core i7-7820XLimited
  • No dedicated AI acceleration hardware
  • AVX-512 can help certain CPU-bound inference tasks
  • Most modern AI workloads are better served by GPUs

Content Creation

Intel Core i7-7740XAdequate
Light Photo EditingOccasional Video EditingBasic 3DCode Compilation
Intel Core i7-7820XVery Good
Adobe Premiere ProDaVinci ResolveBlenderCinema 4DAfter Effects

Gaming

Intel Core i7-7740XVery Good
  • Strong single-threaded core performance keeps frame rates competitive in many titles
  • Best paired with mid-to-high-end discrete GPUs
  • Modern gaming CPUs with more cores and faster memory often deliver better 1% lows
Intel Core i7-7820XGood
  • Capable of high-refresh gaming with a strong GPU
  • Single-core boost reaches up to 4.5 GHz on favored cores
  • Modern CPUs offer better gaming efficiency and higher IPC

Industry Impact

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

Best CPU by Use Case

1080p/1440p Gaming
Very Good
Enthusiast Overclocking
Good
Legacy X299 Reuse
Good
General Productivity
Adequate
Heavy Multi-threaded Workloads
Poor
4K Video Editing
Very Good
3D Rendering
Very Good
Software Compilation
Very Good
Virtualization
Good
Gaming
Good

Target Audience

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

Strengths & Weaknesses

Intel Core i7-7740X

Pros

  • High out-of-box clocks
  • Unlocked for overclocking
  • X299 platform offers flexible chipset PCIe lanes and storage options
  • Strong single-threaded performance for its era
  • Can breathe life into idle LGA2066 boards

Cons

  • Quad core count limits multi-threaded performance
  • Only 16 CPU PCIe lanes
  • No integrated graphics
  • 112 W TDP for four cores is relatively power-hungry
  • Platform is discontinued with limited future upgrade options
Intel Core i7-7820X

Pros

  • 8 cores and 16 threads for multi-threaded workloads
  • Quad-channel DDR4 memory increases bandwidth
  • 28 PCIe 3.0 lanes plus chipset lanes for expansion
  • Turbo Boost Max 3.0 for higher single-core boosts
  • AVX-512 support for optimized workloads
  • Unlocked multiplier for overclocking

Cons

  • High 140 W TDP and power consumption
  • No integrated graphics
  • Only 28 CPU PCIe lanes, limiting multi-GPU configurations
  • Discontinued platform with limited future upgrades
  • Older 14 nm process versus modern smaller nodes

Competitors & Alternatives

Intel Core i7-7740X

Intel Core i7-7820X

  • AMD Ryzen 7 1800X

    Creator/Gaming

    Rival
  • AMD Ryzen 7 1700X

    Creator/Gaming

    Rival
  • AMD Ryzen Threadripper 1920X

    Workstation

    Rival
  • AMD Ryzen Threadripper 1950X

    Workstation

    Rival
  • Compare head-to-head
  • More cores, higher efficiency, and DDR5 on a modern mainstream platform.

    Compare head-to-head
  • AMD Ryzen 9 7900
    Alt

    Strong multi-threaded performance with excellent efficiency.

  • AMD Ryzen 9 5900X
    Alt

    12-core AM4 option with strong gaming and creator performance.

  • High-performance mainstream platform with good upgrade path.

    Compare head-to-head
  • AMD Ryzen Threadripper 2950X (used)
    Alt

    Higher core and lane count for workstation-class workloads.

Our Verdict on Each

A niche, high-clock quad-core for X299 that delivers strong single-threaded performance but lacks the PCIe and memory bandwidth of Skylake-X siblings, making sense only at low prices for specific reuse scenarios.

Best for: Reusing an existing LGA2066 board for gaming or general tasks when the CPU is acquired at very low cost.

Read the full review

A competent eight-core HEDT chip with strong multi-threaded performance and platform expansion, though high power draw and limited PCIe lanes compared to higher-tier X299 CPUs make it a niche choice today.

Best for: Used-market upgrade for an existing X299 build with quad-channel DDR4 and a need for more cores than mainstream.

Read the full review

Frequently Asked Questions

Which is better, Intel Core i7-7740X or Intel Core i7-7820X?

Based on our editorial ratings, the Intel Core i7-7820X comes out ahead with a score of 7.5/10. That said, the best choice depends on your workload — check the spec and performance breakdown above for gaming, productivity and efficiency differences.

Which uses less power?

The Intel Core i7-7740X has the lowest rated TDP. Power draw across these chips: Intel Core i7-7740X (112 W), Intel Core i7-7820X (140 W).

Do Intel Core i7-7740X and Intel Core i7-7820X use the same socket?

Yes — all of these CPUs use the LGA2066 socket, so they share compatible motherboards.

Which has more cores?

The Intel Core i7-7820X has the most cores. Core counts: Intel Core i7-7740X (4 cores), Intel Core i7-7820X (8 cores).