i5-6400 vs i7-3940XM

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Aggregate performance score

Core i7-3940XM
2012
4 cores / 8 threads, 55 Watt
3.68
+7.9%
Core i5-6400
2015
4 cores / 4 threads, 65 Watt
3.41

Core i7-3940XM outperforms Core i5-6400 by a small 8% based on our aggregate benchmark results.

Primary details

Comparing Core i7-3940XM and Core i5-6400 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking14971565
Place by popularitynot in top-100not in top-100
Cost-effectiveness evaluationno data0.78
Market segmentLaptopDesktop processor
SeriesIntel Core i7Intel Core i5
Power efficiency6.334.96
Architecture codenameIvy Bridge (2012−2013)Skylake (2015−2016)
Release date3 September 2012 (12 years ago)2 July 2015 (9 years ago)
Launch price (MSRP)$1,096$187

Cost-effectiveness evaluation

Performance per price, higher is better.

no data

Detailed specifications

Core i7-3940XM and Core i5-6400 basic parameters such as number of cores, number of threads, base frequency and turbo boost clock, lithography, cache size and multiplier lock state. These parameters indirectly say of CPU speed, though for more precise assessment you have to consider their test results.

Physical cores4 (Quad-Core)4 (Quad-Core)
Threads84
Base clock speed3 GHz2.7 GHz
Boost clock speed3.9 GHz3.3 GHz
Bus typeno dataDMI 3.0
Bus rate5 GT/s4 × 8 GT/s
Multiplierno data27
L1 cache64K (per core)64K (per core)
L2 cache256K (per core)256K (per core)
L3 cache8 MB (shared)6 MB (shared)
Chip lithography22 nm14 nm
Die size160 mm2177 mm2
Maximum core temperature105 °Cno data
Maximum case temperature (TCase)no data72 °C
Number of transistors1,400 millionno data
64 bit support++
Windows 11 compatibility--
Unlocked multiplier+-

Compatibility

Information on Core i7-3940XM and Core i5-6400 compatibility with other computer components: motherboard (look for socket type), power supply unit (look for power consumption) etc. Useful when planning a future computer configuration or upgrading an existing one. Note that power consumption of some processors can well exceed their nominal TDP, even without overclocking. Some can even double their declared thermals given that the motherboard allows to tune the CPU power parameters.

Number of CPUs in a configuration11 (Uniprocessor)
SocketFCPGA988FCLGA1151
Power consumption (TDP)55 Watt65 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i7-3940XM and Core i5-6400. You'll probably need this information if you require some particular technology.

Instruction set extensionsIntel® AVXIntel® SSE4.1, Intel® SSE4.2, Intel® AVX2
AES-NI++
AVX++
vPro++
Enhanced SpeedStep (EIST)++
My WiFi+no data
Turbo Boost Technology2.02.0
Hyper-Threading Technology+-
Idle States++
Thermal Monitoring++
Flex Memory Access+no data
Demand Based Switching-no data
FDI+no data
Fast Memory Access+no data

Security technologies

Core i7-3940XM and Core i5-6400 technologies aimed at improving security, for example, by protecting against hacks.

TXT+-
EDB++
Secure Keyno data+
MPX-+
Identity Protection++
SGXno dataYes with Intel® ME
OS Guardno data+
Anti-Theft+no data

Virtualization technologies

Virtual machine speed-up technologies supported by Core i7-3940XM and Core i5-6400 are enumerated here.

AMD-V++
VT-d++
VT-x++
EPT++

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i7-3940XM and Core i5-6400. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory typesDDR3DDR3, DDR4
Maximum memory size32 GB64 GB
Max memory channels22
Maximum memory bandwidth25.6 GB/s34.134 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card
Compare
Intel HD Graphics 4000Intel HD Graphics 530
Max video memoryno data64 GB
Quick Sync Video++
Clear Videono data+
Clear Video HD++
Graphics max frequency1.35 GHz950 MHz
InTru 3D++

Graphics interfaces

Available interfaces and connections of Core i7-3940XM and Core i5-6400 integrated GPUs.

Number of displays supported33
eDP++
DisplayPort++
HDMI++
DVIno data+
SDVO+no data
CRT+no data

Graphics image quality

Maximum display resolutions supported by Core i7-3940XM and Core i5-6400 integrated GPUs, including resolutions over different interfaces.

4K resolution supportno data+
Max resolution over HDMI 1.4no data4096x2304@24Hz
Max resolution over eDPno data4096x2304@60Hz
Max resolution over DisplayPortno data4096x2304@60Hz
Max resolution over VGAno dataN/A

Graphics API support

APIs supported by Core i7-3940XM and Core i5-6400 integrated GPUs, sometimes API versions are included.

DirectXno data12
OpenGLno data4.5

Peripherals

Specifications and connection of peripherals supported by Core i7-3940XM and Core i5-6400.

PCIe version3.03.0
PCI Express lanes1616

Synthetic benchmark performance

Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.


Combined synthetic benchmark score

This is our combined benchmark performance rating. We are regularly improving our combining algorithms, but if you find some perceived inconsistencies, feel free to speak up in comments section, we usually fix problems quickly.

i7-3940XM 3.68
+7.9%
i5-6400 3.41

Passmark

Passmark CPU Mark is a widespread benchmark, consisting of 8 different types of workload, including integer and floating point math, extended instructions, compression, encryption and physics calculation. There is also one separate single-threaded scenario measuring single-core performance.

i7-3940XM 5840
+7.8%
i5-6400 5417

GeekBench 5 Single-Core

GeekBench 5 Single-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses only a single CPU core.

i7-3940XM 644
i5-6400 1125
+74.7%

GeekBench 5 Multi-Core

GeekBench 5 Multi-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses all available CPU cores.

i7-3940XM 2023
i5-6400 3063
+51.4%

Cinebench 10 32-bit single-core

Cinebench R10 is an ancient ray tracing benchmark for processors by Maxon, authors of Cinema 4D. Its single core version uses just one CPU thread to render a futuristic looking motorcycle.

i7-3940XM 5252
+3.2%
i5-6400 5088

Cinebench 10 32-bit multi-core

Cinebench Release 10 Multi Core is a variant of Cinebench R10 using all the processor threads. Possible number of threads is limited by 16 in this version.

i7-3940XM 20564
+12.4%
i5-6400 18297

wPrime 32

wPrime 32M is a math multi-thread processor test, which calculates square roots of first 32 million integer numbers. Its result is measured in seconds, so that the less is benchmark result, the faster the processor.

i7-3940XM 6.98
+50.1%
i5-6400 10.48

Cinebench 11.5 64-bit multi-core

Cinebench Release 11.5 Multi Core is a variant of Cinebench R11.5 which uses all the processor threads. A maximum of 64 threads is supported in this version.

i7-3940XM 7
+25.8%
i5-6400 6

Cinebench 11.5 64-bit single-core

Cinebench R11.5 is an old benchmark by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version loads a single thread with ray tracing to render a glossy room full of crystal spheres and light sources.

i7-3940XM 1.62
+7.3%
i5-6400 1.51

TrueCrypt AES

TrueCrypt is a discontinued piece of software that was widely used for on-the-fly-encryption of disk partitions, now superseded by VeraCrypt. It contains several embedded performance tests, one of them being TrueCrypt AES, which measures data encryption speed using AES algorithm. Result is encryption speed in gigabytes per second.

i7-3940XM 3.7
+37%
i5-6400 2.7

x264 encoding pass 2

x264 Pass 2 is a slower variant of x264 video compression that produces a variable bit rate output file, which results in better quality since the higher bit rate is used when it is needed more. Benchmark result is still measured in frames per second.  

i7-3940XM 41
+19.8%
i5-6400 34

x264 encoding pass 1

x264 version 4.0 is a video encoding benchmark uses MPEG 4 x264 compression method to compress a sample HD (720p) video. Pass 1 is a faster variant that produces a constant bit rate output file. Its result is measured in frames per second, which means how many frames of the source video file were encoded per second.  

i7-3940XM 161
+7.3%
i5-6400 150

Gaming performance

Pros & cons summary


Performance score 3.68 3.41
Integrated graphics card 1.18 2.60
Recency 3 September 2012 2 July 2015
Threads 8 4
Chip lithography 22 nm 14 nm
Power consumption (TDP) 55 Watt 65 Watt

i7-3940XM has a 7.9% higher aggregate performance score, 100% more threads, and 18.2% lower power consumption.

i5-6400, on the other hand, has 120.3% faster integrated GPU, an age advantage of 2 years, and a 57.1% more advanced lithography process.

Given the minimal performance differences, no clear winner can be declared between Core i7-3940XM and Core i5-6400.

Be aware that Core i7-3940XM is a notebook processor while Core i5-6400 is a desktop one.


Should you still have questions on choice between Core i7-3940XM and Core i5-6400, ask them in Comments section, and we shall answer.

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Intel Core i7-3940XM
Core i7-3940XM
Intel Core i5-6400
Core i5-6400

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Community ratings

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Questions & comments

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