CPU Comparison

Intel Core i5-7640X X-series vs Intel Core i7-7740X

A side-by-side comparison of specs, performance and value. The Intel Core i5-7640X is a quad-core, four-thread desktop processor on the LGA2066 platform with base and boost clocks of 4.0 GHz and 4.2 GHz, respectively, dual-channel DDR4-2666 memory, and 16 PCIe 3.0 lanes.

Intel · Core X-Series
Intel Core i5-7640X X-series
4C / 4T4.2 GHz112 W
6
Full review
Top pick
Intel · Core X-Series
Intel Core i7-7740X
4C / 8T4.5 GHz112 W
7
Full review

The Bottom Line

Overview & Launch

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Platform superseded by Skylake-X and later HEDT/enthusiast lines

Specifications Compared

Cores & Clocks
Cores
4
4
Threads
4
8
Base Clock
4 GHz
4.3 GHz
Boost Clock
4.2 GHz
4.5 GHz
Cache & Power
L3 Cache
6 MB
8 MB
TDP
112 W
112 W
Architecture
Architecture
Kaby Lake-X
Kaby Lake-X
Process Node
14 nm
14 nm
Memory
Memory Type
DDR4
DDR4
Memory Speed
DDR4-2666
DDR4-2666
Memory Channels
Dual (2)
Dual (2)
Max Memory
64 GB
64 GB
Platform & I/O
Socket
FCLGA2066
LGA2066
PCIe Version
3.0
PCIe 3.0
PCIe Lanes
16
16
Integrated GPU
None
None
Unlocked
Yes
Yes

Performance Compared

Productivity

Intel Core i5-7640X X-series 58
Intel Core i7-7740XBest68

Gaming

Intel Core i5-7640X X-series 72
Intel Core i7-7740XBest78

Virtualization

Intel Core i5-7640X X-series 55
Intel Core i7-7740XBest60

Efficiency

Intel Core i5-7640X X-series 59
Intel Core i7-7740XBest62

Specialized Performance

AI / ML

Intel Core i5-7640X X-series Limited
  • No dedicated AI acceleration; CPU-bound inference only.
  • Lacks AVX-512; limited to SSE4.1/4.2 and AVX2 instruction sets.
Intel Core i7-7740XLimited
  • No dedicated AI acceleration hardware
  • Suited only for CPU-bound inference and older ML frameworks

Content Creation

Intel Core i5-7640X X-series Limited
Light Photo EditingBasic Video CutsOccasional 3D
Intel Core i7-7740XAdequate
Light Photo EditingOccasional Video EditingBasic 3DCode Compilation

Gaming

Intel Core i5-7640X X-series Good
  • High clocks help in CPU-bound scenarios, but modern games increasingly benefit from more cores/threads.
  • Requires a discrete GPU; no integrated graphics.
  • Performance comparable to contemporary mainstream Kaby Lake i5s when GPU-bound.
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

Industry Impact

Gaming
Low
Low
Workstations
Low
Low
Content Creation
Low
Low
Virtualization
Low
Low

Best CPU by Use Case

1080p/1440p Gaming
Good (with discrete GPU)
Very Good
Light Workstation
Adequate
Overclocking Experiments
Very Good
Legacy X299 Upgrades
Good
Virtualization
Limited
Enthusiast Overclocking
Good
Legacy X299 Reuse
Good
General Productivity
Adequate
Heavy Multi-threaded Workloads
Poor

Target Audience

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

Strengths & Weaknesses

Intel Core i5-7640X X-series

Pros

  • High base and boost clock speeds
  • Unlocked multiplier for overclocking
  • Supports Intel Optane Memory
  • VT-x and VT-d virtualization support
  • DDR4-2666 dual-channel memory support

Cons

  • No integrated graphics requires a discrete GPU
  • No Hyper-Threading; only four threads
  • Only dual-channel memory on a HEDT platform
  • Only 16 CPU PCIe 3.0 lanes
  • Discontinued platform with limited upgrade options
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

Competitors & Alternatives

Intel Core i5-7640X X-series

  • AMD Ryzen 5 1600

    Mainstream

    Rival
  • AMD Ryzen 5 1500X

    Mainstream

    Rival
  • Intel Core i5-7600K

    Mainstream

    Rival
  • Intel Core i7-7700K

    Mainstream

    Rival
  • Intel Core i7-7740X

    HEDT

    Rival
  • Intel Core i5-8400
    Alt

    Six-core mainstream Coffee Lake with better multi-threaded performance.

  • AMD Ryzen 5 2600
    Alt

    Six cores, 12 threads on AM4 with superior efficiency and upgrade path.

  • Intel Core i5-9600K
    Alt

    Later-generation six-core with higher clocks and improved platform longevity.

  • AMD Ryzen 5 3600
    Alt

    Zen 2 six-core with much higher IPC and efficiency on AM4.

  • Intel Core i5-10600K
    Alt

    Six-core, 12-thread Comet Lake on modern platform with DDR4 and better connectivity.

Intel Core i7-7740X

  • AMD Ryzen 5 1600X

    Gaming & Productivity

    Rival
  • AMD Ryzen 7 1700

    Creator

    Rival
  • Intel Core i7-7700K

    Gaming

    Rival
  • Intel Core i5-7640X

    Gaming

    Rival
  • Intel Core i7-7820X

    Workstation

    Rival
  • Intel Core i7-8700K
    Alt

    More cores and better value for gaming and productivity.

  • AMD Ryzen 7 2700X
    Alt

    Higher multi-threaded performance and efficiency.

  • Intel Core i9-9900K
    Alt

    Strong all-round performance on mainstream platforms.

  • Intel Core i7-9700K
    Alt

    More cores and newer platform features.

  • AMD Ryzen 5 3600
    Alt

    Much better performance per watt and platform longevity.

Our Verdict on Each

A capable but ill-positioned quad-core for the X299 HEDT platform, offering strong clock speeds yet lacking Hyper-Threading, integrated graphics, and the multi-threaded punch of contemporaries; mainly relevant today for specific upgrades or used-market builds.

Best for: Upgrading an existing X299 system on a tight budget or acquiring used parts at low cost

Read the full review

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

Frequently Asked Questions

Which is better, Intel Core i5-7640X X-series or Intel Core i7-7740X?

Based on our editorial ratings, the Intel Core i7-7740X comes out ahead with a score of 7/10. 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 i5-7640X X-series or Intel Core i7-7740X?

For gaming, the Intel Core i7-7740X leads with a gaming performance score of 78/100 among Intel Core i5-7640X X-series and Intel Core i7-7740X.

Do Intel Core i5-7640X X-series and Intel Core i7-7740X use the same socket?

No. They use different sockets (Intel Core i5-7640X X-series : FCLGA2066, Intel Core i7-7740X: LGA2066), so each needs a compatible motherboard.