i5-8257U vs i5-9400H

Primary details

Comparing Core i5-9400H and Core i5-8257U processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	1222	1267
Place by popularity	not in top-100	not in top-100
Market segment	Laptop	Laptop
Series	Intel Core i5	Intel Core i5
Power efficiency	10.47	29.65
Architecture codename	Coffee Lake-H (2018−2019)	Coffee Lake-U (2018−2019)
Release date	23 April 2019 (5 years ago)	10 July 2019 (5 years ago)

Detailed specifications

Core i5-9400H 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	2.5 GHz	1.4 GHz
Boost clock speed	4.3 GHz	3.9 GHz
Bus type	DMI 3.0	no data
Bus rate	4 × 8 GT/s	4 GT/s
Multiplier	25	no data
L1 cache	256 KB	256 KB
L2 cache	1 MB	1 MB
L3 cache	8 MB	6 MB
Chip lithography	14 nm	14 nm
Die size	126 mm2	no data
Maximum core temperature	100 °C	100 °C
64 bit support	+	+
Windows 11 compatibility	+	+

Compatibility

Information on Core i5-9400H 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 (Uniprocessor)	1
Socket	FCBGA1440	FCBGA1528
Power consumption (TDP)	45 Watt	15 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i5-9400H and Core i5-8257U. You'll probably need this information if you require some particular technology.

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

Security technologies

Core i5-9400H and Core i5-8257U technologies aimed at improving security, for example, by protecting against hacks.

TXT	+	-
EDB	+	+
Secure Key	+	+
MPX	+	+
Identity Protection	+	+
SGX	Yes with Intel® ME	Yes with Intel® ME
OS Guard	+	+

Virtualization technologies

Virtual machine speed-up technologies supported by Core i5-9400H 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 i5-9400H and Core i5-8257U. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR4	DDR4
Maximum memory size	128 GB	32 GB
Max memory channels	2	2
Maximum memory bandwidth	44.882 GB/s	37.5 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card Compare	Intel UHD Graphics 630	Intel Iris Plus Graphics 645
Max video memory	64 GB	32 GB
Quick Sync Video	+	+
Clear Video	+	+
Clear Video HD	+	+
Graphics max frequency	1.1 GHz	1.05 GHz
InTru 3D	+	+

Graphics interfaces

Available interfaces and connections of Core i5-9400H and Core i5-8257U integrated GPUs.

Number of displays supported	3	3
eDP	+	+
DisplayPort	+	+
HDMI	+	+
DVI	+	+

Graphics image quality

Maximum display resolutions supported by Core i5-9400H and Core i5-8257U integrated GPUs, including resolutions over different interfaces.

4K resolution support	+	+
Max resolution over HDMI 1.4	4096 x 2304@30Hz	4096x2304@30Hz
Max resolution over eDP	4096 x 2304@60Hz	4096x2304@60Hz
Max resolution over DisplayPort	4096 x 2304@60Hz	4096x2304@60Hz
Max resolution over VGA	N/A	no data

Graphics API support

APIs supported by Core i5-9400H and Core i5-8257U integrated GPUs, sometimes API versions are included.

DirectX	12	12
OpenGL	4.5	4.5

Peripherals

Specifications and connection of peripherals supported by Core i5-9400H 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	4.98	4.70
Integrated graphics card	3.09	4.45
Recency	23 April 2019	10 July 2019
Power consumption (TDP)	45 Watt	15 Watt

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Should you still have questions on choice between Core i5-9400H and Core i5-8257U, ask them in Comments section, and we shall answer.

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