i5-8257U vs i7-3940XM

Primary details

Comparing Core i7-3940XM and Core i5-8257U processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	1479	1263
Place by popularity	not in top-100	not in top-100
Market segment	Laptop	Laptop
Series	Intel Core i7	Intel Core i5
Power efficiency	6.33	29.67
Architecture codename	Ivy Bridge (2012−2013)	Coffee Lake-U (2018−2019)
Release date	3 September 2012 (12 years ago)	10 July 2019 (5 years ago)
Launch price (MSRP)	$1,096	no data

Detailed specifications

Core i7-3940XM and Core i5-8257U 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 cores	4 (Quad-Core)	4 (Quad-Core)
Threads	8	8
Base clock speed	3 GHz	1.4 GHz
Boost clock speed	3.9 GHz	3.9 GHz
Bus rate	5 GT/s	4 GT/s
L1 cache	64K (per core)	256 KB
L2 cache	256K (per core)	1 MB
L3 cache	8 MB (shared)	6 MB
Chip lithography	22 nm	14 nm
Die size	160 mm2	no data
Maximum core temperature	105 °C	100 °C
Number of transistors	1,400 million	no data
64 bit support	+	+
Windows 11 compatibility	-	+
Unlocked multiplier	+	-

Compatibility

Information on Core i7-3940XM and Core i5-8257U 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 configuration	1	1
Socket	FCPGA988	FCBGA1528
Power consumption (TDP)	55 Watt	15 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i7-3940XM and Core i5-8257U. You'll probably need this information if you require some particular technology.

Instruction set extensions	Intel® AVX	Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2
AES-NI	+	+
AVX	+	+
Enhanced SpeedStep (EIST)	+	+
eDRAM	no data	128 MB
Speed Shift	no data	+
My WiFi	+	+
Turbo Boost Technology	2.0	2.0
Hyper-Threading Technology	+	+
Idle States	+	+
Thermal Monitoring	+	+
Flex Memory Access	+	+
Demand Based Switching	-	no data
FDI	+	no data
Fast Memory Access	+	no data

Security technologies

Core i7-3940XM and Core i5-8257U technologies aimed at improving security, for example, by protecting against hacks.

TXT	+	-
EDB	+	+
Secure Key	no data	+
MPX	-	+
Identity Protection	+	+
SGX	no data	Yes with Intel® ME
OS Guard	no data	+
Anti-Theft	+	no data

Virtualization technologies

Virtual machine speed-up technologies supported by Core i7-3940XM and Core i5-8257U 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 i5-8257U. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR3	DDR4
Maximum memory size	32 GB	32 GB
Max memory channels	2	2
Maximum memory bandwidth	25.6 GB/s	37.5 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card Compare	Intel HD Graphics 4000	Intel Iris Plus Graphics 645
Max video memory	no data	32 GB
Quick Sync Video	+	+
Clear Video	no data	+
Clear Video HD	+	+
Graphics max frequency	1.35 GHz	1.05 GHz
InTru 3D	+	+

Graphics interfaces

Available interfaces and connections of Core i7-3940XM and Core i5-8257U integrated GPUs.

Number of displays supported	3	3
eDP	+	+
DisplayPort	+	+
HDMI	+	+
DVI	no data	+
SDVO	+	no data
CRT	+	no data

Graphics image quality

Maximum display resolutions supported by Core i7-3940XM and Core i5-8257U integrated GPUs, including resolutions over different interfaces.

4K resolution support	no data	+
Max resolution over HDMI 1.4	no data	4096x2304@30Hz
Max resolution over eDP	no data	4096x2304@60Hz
Max resolution over DisplayPort	no data	4096x2304@60Hz

Graphics API support

APIs supported by Core i7-3940XM and Core i5-8257U integrated GPUs, sometimes API versions are included.

DirectX	no data	12
OpenGL	no data	4.5

Peripherals

Specifications and connection of peripherals supported by Core i7-3940XM and Core i5-8257U.

PCIe version	3.0	3.0
PCI Express lanes	16	16

Synthetic benchmark performance

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

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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.

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Pros & cons summary

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Performance score	3.82	4.88
Integrated graphics card	1.18	4.44
Recency	3 September 2012	10 July 2019
Chip lithography	22 nm	14 nm
Power consumption (TDP)	55 Watt	15 Watt

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Should you still have questions on choice between Core i7-3940XM and Core i5-8257U, ask them in Comments section, and we shall answer.

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