i5-8400 vs i9-7900X

VS

Aggregate performance score

Core i9-7900X
2017
10 cores / 20 threads, 140 Watt
13.25
+128%
Core i5-8400
2017
6 cores / 6 threads, 65 Watt
5.82

Core i9-7900X outperforms Core i5-8400 by a whopping 128% based on our aggregate benchmark results.

Primary details

Comparing Core i9-7900X and Core i5-8400 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking5601116
Place by popularitynot in top-10068
Cost-effectiveness evaluation2.904.94
Market segmentDesktop processorDesktop processor
SeriesCore i9 (Desktop)Intel Core i5
Power efficiency8.968.47
Architecture codenameSkylake (server) (2017−2018)Coffee Lake-S (2017−2018)
Release date26 June 2017 (7 years ago)5 October 2017 (7 years ago)
Launch price (MSRP)$999$182

Cost-effectiveness evaluation

Performance per price, higher is better.

i5-8400 has 70% better value for money than i9-7900X.

Detailed specifications

Core i9-7900X and Core i5-8400 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 cores10 (Deca-Core)6 (Hexa-Core)
Threads206
Base clock speed3.3 GHz2.8 GHz
Boost clock speed4.5 GHz4 GHz
Bus typeDMI 3.0DMI 3.0
Bus rate4 × 8 GT/s4 × 8 GT/s
Multiplier3328
L1 cache64 KB (per core)64K (per core)
L2 cache1 MB (per core)256K (per core)
L3 cache14 MB (shared)9 MB (shared)
Chip lithography14 nm14 nm
Die sizeno data149 mm2
Maximum core temperature95 °C100 °C
Maximum case temperature (TCase)72 °C72 °C
64 bit support++
Windows 11 compatibility++
Unlocked multiplier+-

Compatibility

Information on Core i9-7900X and Core i5-8400 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 configuration1 (Uniprocessor)1 (Uniprocessor)
SocketSocket R4FCLGA1151
Power consumption (TDP)140 Watt65 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i9-7900X and Core i5-8400. You'll probably need this information if you require some particular technology.

Instruction set extensionsIntel® SSE4.1, Intel® SSE4.2, Intel® AVX2, Intel® AVX-512Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2
AES-NI++
AVX++
vPro++
Enhanced SpeedStep (EIST)++
Turbo Boost Technology2.02.0
Hyper-Threading Technology+-
TSX+-
Idle Statesno data+
Thermal Monitoring-+
Turbo Boost Max 3.0+no data

Security technologies

Core i9-7900X and Core i5-8400 technologies aimed at improving security, for example, by protecting against hacks.

TXTno data-
EDB++
Secure Keyno data+
MPX-+
Identity Protection-+
SGXno dataYes with Intel® ME
OS Guardno data+

Virtualization technologies

Virtual machine speed-up technologies supported by Core i9-7900X and Core i5-8400 are enumerated here.

AMD-V++
VT-d++
VT-x++
EPTno data+

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i9-7900X and Core i5-8400. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory typesDDR4DDR3, DDR4
Maximum memory size128 GB128 GB
Max memory channels42
Maximum memory bandwidth85.33 GB/s42.671 GB/s

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics cardN/AIntel UHD Graphics 630
Max video memoryno data64 GB
Quick Sync Video-+
Clear Videono data+
Clear Video HDno data+
Graphics max frequencyno data1.05 GHz
InTru 3Dno data+

Graphics interfaces

Available interfaces and connections of Core i9-7900X and Core i5-8400 integrated GPUs.

Number of displays supportedno data3

Graphics image quality

Maximum display resolutions supported by Core i9-7900X and Core i5-8400 integrated GPUs, including resolutions over different interfaces.

4K resolution supportno data+
Max resolution over HDMI 1.4no data4096x2304@24Hz
Max resolution over eDPno data4096x2304@60Hz
Max resolution over DisplayPortno data4096x2304@60Hz

Graphics API support

APIs supported by Core i9-7900X and Core i5-8400 integrated GPUs, sometimes API versions are included.

DirectXno data12
OpenGLno data4.5

Peripherals

Specifications and connection of peripherals supported by Core i9-7900X and Core i5-8400.

PCIe version3.03.0
PCI Express lanes4416

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.

i9-7900X 13.25
+128%
i5-8400 5.82

Passmark

Passmark CPU Mark is a widespread benchmark, consisting of 8 different types of workload, including integer and floating point math, extended instructions, compression, encryption and physics calculation. There is also one separate single-threaded scenario measuring single-core performance.

i9-7900X 21046
+128%
i5-8400 9238

GeekBench 5 Single-Core

GeekBench 5 Single-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses only a single CPU core.

i9-7900X 1444
+5.2%
i5-8400 1373

GeekBench 5 Multi-Core

GeekBench 5 Multi-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses all available CPU cores.

i9-7900X 8876
+85%
i5-8400 4799

Cinebench 10 32-bit single-core

Cinebench R10 is an ancient ray tracing benchmark for processors by Maxon, authors of Cinema 4D. Its single core version uses just one CPU thread to render a futuristic looking motorcycle.

i9-7900X 7287
+14.5%
i5-8400 6364

Cinebench 10 32-bit multi-core

Cinebench Release 10 Multi Core is a variant of Cinebench R10 using all the processor threads. Possible number of threads is limited by 16 in this version.

i9-7900X 49738
+61.5%
i5-8400 30790

3DMark06 CPU

3DMark06 is a discontinued DirectX 9 benchmark suite from Futuremark. Its CPU part contains two scenarios, one dedicated to artificial intelligence pathfinding, another to game physics using PhysX package.

i9-7900X 12678
+33.8%
i5-8400 9474

wPrime 32

wPrime 32M is a math multi-thread processor test, which calculates square roots of first 32 million integer numbers. Its result is measured in seconds, so that the less is benchmark result, the faster the processor.

i9-7900X 2.91
+113%
i5-8400 6.2

Cinebench 11.5 64-bit multi-core

Cinebench Release 11.5 Multi Core is a variant of Cinebench R11.5 which uses all the processor threads. A maximum of 64 threads is supported in this version.

i9-7900X 24
+117%
i5-8400 11

Cinebench 15 64-bit multi-core

Cinebench Release 15 Multi Core is a variant of Cinebench R15 which uses all the processor threads.

i9-7900X 2148
+128%
i5-8400 941

Cinebench 15 64-bit single-core

Cinebench R15 (standing for Release 15) is a benchmark made by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version (sometimes called Single-Thread) only uses a single processor thread to render a room full of reflective spheres and light sources.

i9-7900X 193
+13.7%
i5-8400 170

Cinebench 11.5 64-bit single-core

Cinebench R11.5 is an old benchmark by Maxon, authors of Cinema 4D. It was superseded by later versions of Cinebench, which use more modern variants of Cinema 4D engine. The Single Core version loads a single thread with ray tracing to render a glossy room full of crystal spheres and light sources.

i9-7900X 2.2
+15.8%
i5-8400 1.9

TrueCrypt AES

TrueCrypt is a discontinued piece of software that was widely used for on-the-fly-encryption of disk partitions, now superseded by VeraCrypt. It contains several embedded performance tests, one of them being TrueCrypt AES, which measures data encryption speed using AES algorithm. Result is encryption speed in gigabytes per second.

i9-7900X 12.1
+142%
i5-8400 5

x264 encoding pass 2

x264 Pass 2 is a slower variant of x264 video compression that produces a variable bit rate output file, which results in better quality since the higher bit rate is used when it is needed more. Benchmark result is still measured in frames per second.  

i9-7900X 121
+97.1%
i5-8400 61

x264 encoding pass 1

x264 version 4.0 is a video encoding benchmark uses MPEG 4 x264 compression method to compress a sample HD (720p) video. Pass 1 is a faster variant that produces a constant bit rate output file. Its result is measured in frames per second, which means how many frames of the source video file were encoded per second.  

i9-7900X 217
i5-8400 224
+3.1%

WinRAR 4.0

WinRAR 4.0 is an outdated version of a popular file archiver. It contains an internal speed test, using 'Best' setting of RAR compression on large chunks of randomly generated data. Its results are measured in kilobytes per second.

i9-7900X 5918
+14.4%
i5-8400 5173

Geekbench 4.0 64-bit multi-core

i9-7900X 27533
+41.2%
i5-8400 19500

Geekbench 4.0 64-bit single-core

i9-7900X 4987
i5-8400 4996
+0.2%

Gaming performance

Pros & cons summary


Performance score 13.25 5.82
Recency 26 June 2017 5 October 2017
Physical cores 10 6
Threads 20 6
Power consumption (TDP) 140 Watt 65 Watt

i9-7900X has a 127.7% higher aggregate performance score, and 66.7% more physical cores and 233.3% more threads.

i5-8400, on the other hand, has an age advantage of 3 months, and 115.4% lower power consumption.

The Core i9-7900X is our recommended choice as it beats the Core i5-8400 in performance tests.


Should you still have questions on choice between Core i9-7900X and Core i5-8400, ask them in Comments section, and we shall answer.

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Intel Core i9-7900X
Core i9-7900X
Intel Core i5-8400
Core i5-8400

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Community ratings

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Questions & comments

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