i9-9900KF vs i5-8400T

Primary details

Comparing Core i5-8400T and Core i9-9900KF processor market type (desktop or notebook), architecture, sales start time and price.

Place in performance ranking	1248	657
Place by popularity	not in top-100	not in top-100
Cost-effectiveness evaluation	5.46	8.98
Market segment	Desktop processor	Desktop processor
Series	Intel Core i5	Intel Core i9
Architecture codename	Coffee Lake (2017−2019)	Coffee Lake-R (2018−2019)
Release date	2 April 2018 (6 years ago)	7 January 2019 (5 years ago)
Launch price (MSRP)	$182	$488

Cost-effectiveness evaluation

Performance per price, higher is better.

i9-9900KF has 64% better value for money than i5-8400T.

Detailed specifications

Core i5-8400T and Core i9-9900KF 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)	8 (Octa-Core)
Threads	6	16
Base clock speed	1.7 GHz	3.6 GHz
Boost clock speed	3.3 GHz	5 GHz
Bus type	DMI 3.0	DMI 3.0
Bus rate	4 × 8 GT/s	4 × 8 GT/s
Multiplier	17	no data
L1 cache	384 KB	512 KB
L2 cache	1.5 MB	2 MB
L3 cache	9 MB (shared)	16 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	72 °C
64 bit support	+	+
Windows 11 compatibility	+	+
Unlocked multiplier	-	+

Compatibility

Information on Core i5-8400T and Core i9-9900KF 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	FCLGA1151
Power consumption (TDP)	35 Watt	95 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i5-8400T and Core i9-9900KF. 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)	+	+
Turbo Boost Technology	2.0	2.0
Hyper-Threading Technology	-	+
TSX	-	+
Idle States	+	+
Thermal Monitoring	+	+
Status	Discontinued	Discontinued

Security technologies

Core i5-8400T and Core i9-9900KF 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 i5-8400T and Core i9-9900KF are enumerated here.

VT-d	+	+
VT-x	+	+
EPT	+	+

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i5-8400T and Core i9-9900KF. Depending on the motherboard, higher memory frequencies may be supported.

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

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card	Intel UHD Graphics 630	no data
Max video memory	64 GB	no data
Quick Sync Video	+	-
Clear Video	+	no data
Clear Video HD	+	no data
Graphics max frequency	1.05 GHz	no data
InTru 3D	+	no data

Graphics interfaces

Available interfaces and connections of Core i5-8400T and Core i9-9900KF integrated GPUs.

Number of displays supported

3

no data

Graphics image quality

Maximum display resolutions supported by Core i5-8400T and Core i9-9900KF integrated GPUs, including resolutions over different interfaces.

4K resolution support	+	no data
Max resolution over HDMI 1.4	4096x2304@24Hz	no data
Max resolution over eDP	4096x2304@60Hz	no data
Max resolution over DisplayPort	4096x2304@60Hz	no data

Graphics API support

APIs supported by Core i5-8400T and Core i9-9900KF 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 i5-8400T and Core i9-9900KF.

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.

Pros & cons summary

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Performance score	4.82	11.84
Recency	2 April 2018	7 January 2019
Physical cores	6	8
Threads	6	16
Power consumption (TDP)	35 Watt	95 Watt

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Should you still have questions on choice between Core i5-8400T and Core i9-9900KF, ask them in Comments section, and we shall answer.

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