i7-8665U vs i5-9400

Primary details

Comparing Core i5-9400 and Core i7-8665U processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	1114	1448
Place by popularity	not in top-100	not in top-100
Cost-effectiveness evaluation	8.50	no data
Market segment	Desktop processor	Laptop
Series	Intel Core i5	Intel Core i7
Power efficiency	8.59	24.79
Architecture codename	Coffee Lake (2017−2019)	Whiskey Lake-U (2018−2019)
Release date	7 January 2019 (5 years ago)	16 April 2019 (5 years ago)
Launch price (MSRP)	$182	$409

Cost-effectiveness evaluation

Performance per price, higher is better.

Detailed specifications

Core i5-9400 and Core i7-8665U 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	6 (Hexa-Core)	4 (Quad-Core)
Threads	6	8
Base clock speed	2.9 GHz	1.9 GHz
Boost clock speed	4.1 GHz	4.8 GHz
Bus type	DMI 3.0	OPI
Bus rate	4 × 8 GT/s	4 GT/s
Multiplier	29	19
L1 cache	384 KB	256 KB
L2 cache	1.5 MB	1 MB
L3 cache	9 MB (shared)	8 MB (shared)
Chip lithography	14 nm	14 nm
Die size	149 mm2	no data
Maximum core temperature	100 °C	100 °C
Maximum case temperature (TCase)	72 °C	no data
64 bit support	+	+
Windows 11 compatibility	+	+

Compatibility

Information on Core i5-9400 and Core i7-8665U 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 (Uniprocessor)
Socket	FCLGA1151	FCBGA1528
Power consumption (TDP)	65 Watt	15 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i5-9400 and Core i7-8665U. 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	+	+
Enhanced SpeedStep (EIST)	+	+
Speed Shift	no data	+
My WiFi	no data	+
Turbo Boost Technology	2.0	2.0
Hyper-Threading Technology	-	+
TSX	-	+
Idle States	+	+
Thermal Monitoring	+	+
Flex Memory Access	no data	+
SIPP	-	+
Smart Response	no data	+

Security technologies

Core i5-9400 and Core i7-8665U 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 i5-9400 and Core i7-8665U are enumerated here.

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

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i5-9400 and Core i7-8665U. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR4-2666	DDR4
Maximum memory size	128 GB	64 GB
Max memory channels	2	2
Maximum memory bandwidth	42.671 GB/s	38.397 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card Compare	Intel UHD Graphics 630	Intel UHD Graphics for 8th Generation Intel Processors
Max video memory	64 GB	32 GB
Quick Sync Video	+	+
Clear Video	+	+
Clear Video HD	+	+
Graphics max frequency	1.05 GHz	1.15 GHz
InTru 3D	+	no data

Graphics interfaces

Available interfaces and connections of Core i5-9400 and Core i7-8665U integrated GPUs.

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

Graphics image quality

Maximum display resolutions supported by Core i5-9400 and Core i7-8665U integrated GPUs, including resolutions over different interfaces.

4K resolution support	+	+
Max resolution over HDMI 1.4	4096 x 2304@24Hz	4096 x 2304@24Hz
Max resolution over eDP	4096 x 2304@60Hz	4096 x 2304@60Hz
Max resolution over DisplayPort	4096 x 2304@60Hz	4096 x 2304@60Hz

Graphics API support

APIs supported by Core i5-9400 and Core i7-8665U integrated GPUs, sometimes API versions are included.

DirectX	12	12
OpenGL	4.5	4.5

Peripherals

Specifications and connection of peripherals supported by Core i5-9400 and Core i7-8665U.

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	5.90	3.93
Integrated graphics card	3.09	5.58
Recency	7 January 2019	16 April 2019
Physical cores	6	4
Threads	6	8
Power consumption (TDP)	65 Watt	15 Watt

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Should you still have questions on choice between Core i5-9400 and Core i7-8665U, ask them in Comments section, and we shall answer.

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