Quick Verdict
A legendary mobile CPU that hit 4.0 GHz and offered unlocked overclocking, providing desktop-level performance for laptops.
Overview
Launch
Jan 20th, 2014
Status
End-of-lifeGeneration
Core i7 Extreme (Haswell)
Market
Mobile
The Intel Core i7-4940MX is an extreme edition mobile processor released in early 2014 as the absolute top-end of the Haswell mobile lineup. Designed for the most powerful gaming and workstation laptops, it features four cores and eight threads. Like its predecessor, it boasts an unlocked multiplier for enthusiast overclocking. It operates at a base clock of 3.1 GHz and can turbo boost up to 4.0 GHz, a significant milestone for mobile CPUs at the time. It includes a full 8 MB of L3 SmartCache and carries a 57-watt thermal design power. The integrated Intel HD 4600 graphics are present, though such systems invariably use discrete GPUs. This CPU was the ultimate mobile processor for 2014, catering to a niche audience of hardcore enthusiasts willing to pay a premium for unlocked mobile overclocking and maximum multi-threaded performance.
The Intel Core i7-4940MX is a Haswell extreme edition processor with 4 cores and 8 threads. It features a base clock of 3.1 GHz and boosts up to 4.
0 GHz. With an unlocked multiplier and 8MB of cache, it was the ultimate mobile CPU for overclocking enthusiasts in 2014.
Specifications
Performance
8 threads and 4.0 GHz boost make quick work of compiling and rendering.
Good for running VMs, though limited by mobile platform constraints.
Excellent for older games and can handle modern eSports easily with a discrete GPU.
57W TDP is very power-hungry for a mobile chip, resulting in poor battery life.
- •Won't bottleneck 2014-era GPUs
- •Can be overclocked for extra FPS
- •Requires massive laptop cooling
- •No AI hardware
- •CPU inference is slow
Architecture
22nm
Process Node
Haswell
Codename
4C / 8T
Core Config
8 MB
L3 Cache
57 W
TDP
Architecture Overview
Built on Intel's 22nm Haswell microarchitecture, the Core i7-4940MX is engineered for extreme mobile performance. It features a 4-core, 8-thread design via Hyper-Threading. The critical architectural feature is its unlocked multiplier, allowing enthusiasts to manually tune clock speeds. It includes the full 8 MB of L3 SmartCache. The chip integrates the Intel HD 4600 graphics engine, dynamically scaling between 400 MHz and 1350 MHz. Haswell's integrated voltage regulator (FIVR) aids in stabilizing voltages during overclocking. The architecture supports dual-channel DDR3 memory at 1600 MT/s and provides 16 PCIe 3.0 lanes. Tuned for a 57W TDP, the 4940MX utilizes a higher power envelope to sustain maximum boost clocks and accommodate overclocking headroom. Its ability to hit 4.0 GHz out of the box made it a marvel of 22nm silicon engineering for the mobile sector.
CPU Design
4 cores, 8 threads, unlocked.
Memory Subsystem
Dual-channel DDR3-1600.
PCIe & I/O
16 PCIe 3.0 lanes.
Overclocking
Fully unlocked multiplier.
- Higher base and turbo clocks
- Refined 22nm process
Key Highlights
- 4.0 GHz turbo boost
- Unlocked multiplier
- Full 8MB L3 cache
- Removable PGA socket
- Extremely high 57W TDP
- Runs very hot
- Expensive launch price
- Poor battery life
History
Launched in January 2014, the Core i7-4940MX was a minor refresh of the 4930MX, designed to maintain Intel's absolute dominance in the mobile extreme edition segment. By pushing the turbo boost to 4.0 GHz, Intel achieved a significant milestone in mobile CPU clock speeds.
The 4940MX was featured in the most expensive, heavily cooled gaming laptops of 2014. It represented the final hurrah for the 4-core mobile extreme edition before the Broadwell architecture shifted focus slightly towards efficiency. This processor was a status symbol, offering unparalleled performance for users who refused to compromise on laptop speed.
Its release underscored the intense competition in the high-end gaming laptop market, where manufacturers constantly sought ways to cram desktop-class performance into portable form factors, regardless of power consumption or heat output.
Improvements over Previous Generation
- Higher base and turbo clocks
- Refined 22nm process
Alternatives & Competitors
Should You Buy It?
Recommended for the right buyer
Collecting vintage gaming laptops or extreme budget used systems.
Avoid if…
- Buying a new laptop
- Need battery life
- Modern gaming
Use Cases
Interesting Facts
Features an unlocked multiplier for overclocking.
Hits 4.0 GHz on turbo boost.
Has a massive 57W TDP for a mobile chip.
Launch price was $1096.
Integrated graphics boost up to 1350 MHz.
Uses the PGA946 socket.
Contains 1.4 billion transistors.
Die size is 177 mm².
Launched in January 2014.
Part number SR1PP.
People Also Ask
Is the Core i7-4940MX good for gaming?
Yes, it was the top mobile gaming CPU in 2014. It still handles older games well.
Can the Core i7-4940MX be overclocked?
Yes, it features an unlocked multiplier, a rarity for laptops.
What socket does the i7-4940MX use?
It uses the Intel Socket G3 (PGA946).
What is the TDP of the Core i7-4940MX?
57 Watts, which is very high for a mobile processor.
Can I upgrade the i7-4940MX in my laptop?
Yes, it uses a PGA socket, so it can be physically removed and upgraded.
Does the i7-4940MX support DDR4?
No, it supports DDR3 only.
How many cores does it have?
4 cores and 8 threads.
Is it compatible with Windows 11?
Officially not supported, but can run it.
What are the integrated graphics?
Intel HD Graphics 4600.
What is the max turbo frequency?
4.0 GHz.
Frequently Asked Questions
Does the i7-4940MX support Hyper-Threading?
Yes, 4 cores and 8 threads.
Does it support ECC memory?
No, ECC is not supported.
What is the L3 cache size?
8 MB.
What chipsets are compatible?
HM86, HM87, QM87.
Is it good for video editing?
It can handle 1080p editing well, but 4K will be slow.
Can it run 4K video?
Yes, via hardware decoding on the iGPU.
Does it support Intel Optane?
No, Optane was introduced much later.
What is the base clock?
3.1 GHz.
Does it have vPro?
Yes, this SKU supports vPro.
Is it unlocked?
Yes, the multiplier is fully unlocked.