i9-9940X vs i5-8600K

Primary details

Comparing Core i5-8600K and Core i9-9940X processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	1043	347
Place by popularity	not in top-100	not in top-100
Cost-effectiveness evaluation	4.25	5.44
Market segment	Desktop processor	Desktop processor
Series	Intel Core i5	Intel Core i9
Power efficiency	6.40	10.10
Architecture codename	Coffee Lake-S (2017−2018)	Skylake (server) (2017−2019)
Release date	24 September 2017 (7 years ago)	19 October 2018 (6 years ago)
Launch price (MSRP)	$257	$1,387

Cost-effectiveness evaluation

Performance per price, higher is better.

i9-9940X has 28% better value for money than i5-8600K.

Detailed specifications

Core i5-8600K and Core i9-9940X 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)	14 (Tetradeca-Core)
Threads	6	28
Base clock speed	3.6 GHz	3.3 GHz
Boost clock speed	4.3 GHz	4.5 GHz
Bus type	DMI 3.0	DMI 3.0
Bus rate	4 × 8 GT/s	4 × 8 GT/s
Multiplier	36	33
L1 cache	384 KB	64 KB (per core)
L2 cache	1.5 MB	1 MB (per core)
L3 cache	9 MB (shared)	19.25 MB (shared)
Chip lithography	14 nm	14 nm
Die size	149 mm2	484 mm2
Maximum core temperature	100 °C	88 °C
Maximum case temperature (TCase)	72 °C	no data
64 bit support	+	+
Windows 11 compatibility	+	+
Unlocked multiplier	+	+

Compatibility

Information on Core i5-8600K and Core i9-9940X 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	FCLGA2066
Power consumption (TDP)	95 Watt	165 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i5-8600K and Core i9-9940X. 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, Intel® AVX-512
AES-NI	+	+
AVX	+	+
vPro	+	no data
Enhanced SpeedStep (EIST)	+	+
Turbo Boost Technology	2.0	2.0
Hyper-Threading Technology	+	+
TSX	+	+
Idle States	+	no data
Thermal Monitoring	+	-
SIPP	+	-
Turbo Boost Max 3.0	no data	+

Security technologies

Core i5-8600K and Core i9-9940X technologies aimed at improving security, for example, by protecting against hacks.

TXT	+	no data
EDB	+	+
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 i5-8600K and Core i9-9940X 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 i5-8600K and Core i9-9940X. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR3, DDR4	DDR4-2666
Maximum memory size	128 GB	128 GB
Max memory channels	2	4
Maximum memory bandwidth	42.671 GB/s	85.33 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card	Intel UHD Graphics 630	N/A
Max video memory	64 GB	no data
Quick Sync Video	+	-
Clear Video	+	no data
Clear Video HD	+	no data
Graphics max frequency	1.15 GHz	no data
InTru 3D	+	no data

Graphics interfaces

Available interfaces and connections of Core i5-8600K and Core i9-9940X integrated GPUs.

Number of displays supported

3

no data

Graphics image quality

Maximum display resolutions supported by Core i5-8600K and Core i9-9940X 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 i5-8600K and Core i9-9940X 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 i5-8600K and Core i9-9940X.

PCIe version	3.0	3.0
PCI Express lanes	16	44

Synthetic benchmark performance

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

---

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

---

Performance score	6.67	18.28
Recency	24 September 2017	19 October 2018
Physical cores	6	14
Threads	6	28
Power consumption (TDP)	95 Watt	165 Watt

---

Should you still have questions on choice between Core i5-8600K and Core i9-9940X, ask them in Comments section, and we shall answer.

Vote for your favorite

Do you think we are right or mistaken in our choice? Vote by clicking "Like" button near your favorite CPU.

---