CPU Comparison
Core i7-7740X vs Intel Core i5-7640X X-series
A side-by-side comparison of specs, performance and value. The Intel Core i7-7740X is a unique high-end desktop (HEDT) processor launched in June 2017. Based on the Kaby Lake-X architecture, it is essentially a mainstream quad-core die repurposed for the enthusiast LGA 2066 socket. Featuring 4 cores and 8 threads, it operates at a high base frequency of 4.3 GHz and boosts up to 4.6 GHz, catering specifically to users seeking maximum single-threaded performance. The X suffix denotes an unlocked multiplier, allowing for further overclocking. With a 112W TDP, it demands robust cooling. Notably, it lacks integrated graphics and does not support quad-channel memory, differentiating it from true HEDT Skylake-X parts. It includes 8MB of L3 cache and supports dual-channel DDR4 memory. The i7-7740X was a controversial product, offering little practical benefit over the cheaper LGA 1151 i7-7700K, but it allowed enthusiasts to access high clock speeds on the X299 platform, albeit with a limited feature set.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
Four cores with no Hyper-Threading limit multi-threaded workloads; better suited to light productivity than heavy rendering or compiling.
Gaming
Sufficient for high-refresh gaming when paired with a strong GPU, but constrained by lack of Hyper-Threading and limited core count in modern titles.
Virtualization
Can run modest VM loads, but core and thread count make it less ideal for multiple concurrent VMs.
Efficiency
High 112 W TDP for a quad-core design results in lower performance-per-watt than newer mainstream platforms.
Specialized Performance
AI / ML
No data
- No dedicated AI acceleration; CPU-bound inference only.
- Lacks AVX-512; limited to SSE4.1/4.2 and AVX2 instruction sets.
Content Creation
No data
Gaming
No data
- 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.
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
Pros
- High single-core frequencies
- Unlocked for overclocking
- Access to X299 chipset features
Cons
- Only 4 cores on an HEDT platform
- Limited to dual-channel memory
- No integrated graphics
- Poor value compared to true HEDT or mainstream parts
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
Competitors & Alternatives
Core i7-7740X
- Intel Core i7-7700KRival
Performance Desktop
- Compare head-to-headIntel Core i7-7800XRival
High-End Desktop
- AMD Ryzen 7 1800XRival
High-End Desktop
- Intel Core i5-7640XRival
High-End Desktop
- AMD Ryzen 5 1600XRival
Performance Desktop
- AMD Ryzen 7 1700Alt
More cores and better multi-threading for less money.
Actual high-end HEDT performance.
Compare head-to-head- AMD Threadripper 1900XAlt
Better HEDT platform features and core count.
Intel Core i5-7640X X-series
- AMD Ryzen 5 1600Rival
Mainstream
- AMD Ryzen 5 1500XRival
Mainstream
- Compare head-to-headIntel Core i5-7600KRival
Mainstream
- Intel Core i7-7700KRival
Mainstream
- RivalCompare head-to-head
Six-core mainstream Coffee Lake with better multi-threaded performance.
Compare head-to-head- AMD Ryzen 5 2600Alt
Six cores, 12 threads on AM4 with superior efficiency and upgrade path.
Later-generation six-core with higher clocks and improved platform longevity.
Compare head-to-head- AMD Ryzen 5 3600Alt
Zen 2 six-core with much higher IPC and efficiency on AM4.
Six-core, 12-thread Comet Lake on modern platform with DDR4 and better connectivity.
Compare head-to-head
Our Verdict on Each
An oddity in Intel's lineup, offering high clocks but limited core count and features for the HEDT platform. Hard to recommend over mainstream alternatives.
Best for: Niche collection or specific legacy X299 troubleshooting
Read the full reviewA 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 reviewFrequently Asked Questions
Which is faster for gaming, Core i7-7740X or Intel Core i5-7640X X-series?
For gaming, the Intel Core i5-7640X X-series leads with a gaming performance score of 72/100 among Core i7-7740X and Intel Core i5-7640X X-series.
Do Core i7-7740X and Intel Core i5-7640X X-series use the same socket?
No. They use different sockets (Core i7-7740X: LGA 2066, Intel Core i5-7640X X-series: FCLGA2066), so each needs a compatible motherboard.
Which is faster in multi-core benchmarks?
The Core i7-7740X posts the highest multi-core benchmark score. Multi-core results: Core i7-7740X (0). Benchmark figures are approximate and workload-dependent.