CPU Comparison
Intel Core i9-7920X X-series vs Intel Core i9-9940X
A side-by-side comparison of specs, performance and value. The Intel Core i9-7920X is a 12-core, 24-thread high-end desktop processor built on Skylake-X with quad-channel DDR4-2666 memory, up to 44 PCIe 3.0 lanes, and no integrated graphics. Designed for X299 platforms, it targets enthusiasts, creators, and workstation users who need multi-core throughput and I/O expansion in a desktop form factor.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
Gaming
Virtualization
Efficiency
Specialized Performance
AI / ML
- No dedicated AI acceleration hardware.
- Suitable for CPU-based inference or traditional machine learning preprocessing.
- Workloads heavily dependent on modern AI accelerators will run much slower.
- No dedicated AI accelerators; relies on AVX‑512 CPU inference.
- Acceptable for light CPU‑based inference or prototyping, but not competitive with modern CPUs or GPUs with DL Boost / Tensor cores.
Content Creation
Gaming
- Sufficient for high-refresh gaming when paired with a strong GPU.
- Turbo Boost Max 3.0 can elevate single-core performance for less threaded titles.
- Modern gaming CPUs tend to offer better efficiency and higher sustained clocks.
- Strong single‑core clocks up to 4.4 GHz with Turbo Boost Max 3.0 up to 4.5 GHz on favored cores.
- Capable of 144 fps+ esports performance at 1080p with a modern GPU; more GPU‑bound at 1440p and 4K.
- Modern 6–8 core CPUs often match or beat it in games while drawing far less power.
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
Pros
- 12 cores and 24 threads
- Quad-channel DDR4-2666 memory support
- Up to 44 PCIe 3.0 lanes for expansion
- Unlocked multiplier for overclocking
- Turbo Boost Max 3.0 for lightly threaded tasks
- AVX-512 instruction support
- Strong multi-threaded performance for its time
Cons
- High power consumption under load
- No integrated graphics
- Platform (X299/LGA2066) is discontinued
- Newer platforms offer better efficiency and value
- PCIe 3.0 instead of newer generations
Pros
- 14 cores and 28 threads for heavily threaded workloads.
- 44 PCIe 3.0 lanes for multi‑GPU and NVMe setups.
- Quad‑channel DDR4‑2666 with up to 128 GB support.
- AVX‑512 instruction support for specialized compute.
- Unlocked multiplier for enthusiast overclocking.
Cons
- High 165 W TDP and relatively low efficiency vs newer CPUs.
- Older 14 nm Skylake‑X platform with no upgrade path beyond Cascade Lake‑X.
- No integrated graphics; requires a discrete GPU.
- Only 44 PCIe lanes versus 64 on competing Threadripper platforms.
- Discontinued, with limited long‑term platform support.
Competitors & Alternatives
Intel Core i9-7920X X-series
- AMD Ryzen Threadripper 1920XRival
Workstation
- AMD Ryzen Threadripper 1950XRival
Workstation
- AMD Ryzen 9 3900XRival
Creator
- AMD Ryzen 9 3950XRival
Creator
- Compare head-to-headIntel Core i9-10920XRival
Workstation
Cascade Lake-X refresh with improved features and clocks on X299.
Compare head-to-head- AMD Ryzen 9 5900XAlt
Stronger efficiency and gaming performance on AM4 platform.
- AMD Ryzen 9 7900Alt
Modern AM5 platform with DDR5 and PCIe 5.0 for new builds.
- AMD Threadripper 3000/4000 seriesAlt
Higher core counts and more I/O for professional workstations.
- Intel Core i7-14700KAlt
Good mainstream alternative for gaming and content creation with lower power.
Intel Core i9-9940X
- AMD Ryzen Threadripper 2920XRival
HEDT / Workstation
- AMD Ryzen Threadripper 2970WXRival
HEDT / Many‑Core Workstation
- AMD Ryzen 9 3900XRival
High‑End Mainstream / Creator
- Compare head-to-headIntel Core i9-10940XRival
HEDT (Cascade Lake‑X)
- Compare head-to-headIntel Core i9-7940XRival
Previous‑Gen HEDT
- Intel Core i7-14700KAlt
Newer hybrid architecture with similar or better multi‑thread performance and far better efficiency for a new build.
- AMD Ryzen 9 7900Alt
Modern AM5 platform with DDR5 and PCIe 5.0, much better efficiency, and strong creator performance.
Our Verdict on Each
A capable HEDT chip with strong multi-threaded performance and ample I/O, but power-hungry by modern standards and best pursued used or for legacy X299 builds.
Best for: Upgrading or completing an existing LGA2066/X299 build at a low used price
Read the full reviewA capable HEDT CPU with strong multi‑threaded performance and excellent I/O, but outclassed in efficiency and value by newer mainstream and HEDT alternatives.
Best for: Used or discounted X299 workstation builds where you need many cores and PCIe lanes on a budget.
Read the full reviewFrequently Asked Questions
Which is better, Intel Core i9-7920X X-series or Intel Core i9-9940X?
Based on our editorial ratings, the Intel Core i9-9940X 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.
Which uses less power?
The Intel Core i9-7920X X-series has the lowest rated TDP. Power draw across these chips: Intel Core i9-7920X X-series (140 W), Intel Core i9-9940X (165 W).
Do Intel Core i9-7920X X-series and Intel Core i9-9940X use the same socket?
No. They use different sockets (Intel Core i9-7920X X-series: LGA2066, Intel Core i9-9940X: FCLGA2066), so each needs a compatible motherboard.
Which has more cores?
The Intel Core i9-9940X has the most cores. Core counts: Intel Core i9-7920X X-series (12 cores), Intel Core i9-9940X (14 cores).