i5-8420 vs i9-9900K

Primary details

Comparing Core i9-9900K and Core i5-8420 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	675	not rated
Place by popularity	not in top-100	not in top-100
Cost-effectiveness evaluation	7.61	no data
Market segment	Desktop processor	Desktop processor
Series	Core i9 (Desktop)	Intel Core i5
Power efficiency	11.45	no data
Architecture codename	Coffee Lake-R (2018−2019)	Coffee Lake (2017−2019)
Release date	8 October 2018 (6 years ago)	1 September 2018 (6 years ago)
Launch price (MSRP)	$488	no data

Cost-effectiveness evaluation

Performance per price, higher is better.

Detailed specifications

Core i9-9900K and Core i5-8420 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	8 (Octa-Core)	6 (Hexa-Core)
Threads	16	6
Base clock speed	3.6 GHz	2.9 GHz
Boost clock speed	5 GHz	4.1 GHz
Bus type	DMI 3.0	DMI 3.0
Bus rate	4 × 8 GT/s	4 × 8 GT/s
L1 cache	512 KB	384 KB
L2 cache	2 MB	1.5 MB
L3 cache	16 MB (shared)	9 MB (shared)
Chip lithography	14 nm	14 nm
Die size	178 mm2	126 mm2
Maximum core temperature	100 °C	no data
Maximum case temperature (TCase)	72 °C	72 °C
64 bit support	+	+
Windows 11 compatibility	+	-
Unlocked multiplier	+	-

Compatibility

Information on Core i9-9900K and Core i5-8420 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	LGA-1151	1151
Power consumption (TDP)	95 Watt	65 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i9-9900K and Core i5-8420. You'll probably need this information if you require some particular technology.

Instruction set extensions	Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2	no data
AES-NI	+	+
AVX	+	+
vPro	+	no data
Enhanced SpeedStep (EIST)	+	+
Turbo Boost Technology	2.0	no data
Hyper-Threading Technology	+	no data
TSX	+	-
Idle States	+	no data
Thermal Monitoring	+	-
SIPP	+	-

Security technologies

Core i9-9900K and Core i5-8420 technologies aimed at improving security, for example, by protecting against hacks.

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

Virtualization technologies

Virtual machine speed-up technologies supported by Core i9-9900K and Core i5-8420 are enumerated here.

AMD-V	+	-
VT-d	+	+
VT-x	+	+
EPT	+	no data

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i9-9900K and Core i5-8420. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR4	DDR4 Dual-channel
Maximum memory size	128 GB	64 GB
Max memory channels	2	2
Maximum memory bandwidth	44.668 GB/s	42.671 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card	Intel UHD Graphics 630	Intel UHD Graphics 630
Max video memory	64 GB	no data
Quick Sync Video	+	-
Clear Video	+	no data
Clear Video HD	+	no data
Graphics max frequency	1.2 GHz	no data
InTru 3D	+	no data

Graphics interfaces

Available interfaces and connections of Core i9-9900K and Core i5-8420 integrated GPUs.

Number of displays supported

3

no data

Graphics image quality

Maximum display resolutions supported by Core i9-9900K and Core i5-8420 integrated GPUs, including resolutions over different interfaces.

4K resolution support	+	no data
Max resolution over HDMI 1.4	4096 x 2304@24Hz	no data
Max resolution over eDP	4096 x 2304@60Hz	no data
Max resolution over DisplayPort	4096 x 2304@60Hz	no data

Graphics API support

APIs supported by Core i9-9900K and Core i5-8420 integrated GPUs, sometimes API versions are included.

DirectX	12	no data
OpenGL	4.5	no data

Peripherals

Specifications and connection of peripherals supported by Core i9-9900K and Core i5-8420.

PCIe version	3.0	3.0
PCI Express lanes	16	no data

Pros & cons summary

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Recency	8 October 2018	1 September 2018
Physical cores	8	6
Threads	16	6
Power consumption (TDP)	95 Watt	65 Watt

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Should you still have questions on choice between Core i9-9900K and Core i5-8420, ask them in Comments section, and we shall answer.

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