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Intel Core i5-8400 Review: Six Cores On A Budget

How We Test

Test Notes

MSI motherboards, like many others, feature a default Enhanced Turbo feature that allows the processor to run at its maximum Turbo Boost bin on all cores, at all times. For all practical purposes, this is the same as overclocking. The feature only applies to K-series processors, though, so it isn't a factor in our Core i5-8400 testing.

We paired our sample with a Z370-based motherboard, which does support faster memory. Sticking with Intel's official specification, we used DDR4-2666 modules to represent the data rates you'll have access to once B- and H-series motherboards surface.

As far as we can tell on our MSI motherboard, Intel isn't allowing BCLK adjustments. That means the Core i5-8400 locks us down to stock settings.

Comparison Products

Test Systems

We introduced our new test system and methodology in How We Test Graphics Cards. If you'd like more detail about our general approach, check that piece out.

Only our CPU, memory, motherboard, and cooling subsystem are different. The table below summarizes the hardware we used to generate our data.

Test System & Configuration
HardwareGermany Intel LGA 1151 (Z370):Intel Core i5-8600K, Core i5-8400MSI Z370 Gaming Pro Carbon AC2x 8GB Corsair Vengeance DDR4-3200 @ 2666AMD Socket AM4 WorkstationAMD Ryzen 5 1500X, Ryzen 5 1600X, Ryzen 5 1400MSI X370 Tomahawk4x 8GB G.Skill TridentZ DDR4-3200 @ 2667 and 3200 Intel LGA 1151 (Z270)Intel Core i5-7600K, Core i5-7400MSI Z270 Gaming 72x 8GB Corsair Vengeance DDR4-3200 @ 2400 and 3200All SystemsGeForce GTX 1080 Founders Edition (Gaming)Nvidia Quadro P6000 (Workstation)1x 1TB Toshiba OCZ RD400 (M.2, System)2x 960GB Toshiba OCZ TR150 (Storage, Images)be quiet! Dark Power Pro 11, 850W Power SupplyWindows 10 Pro (Creators Update)U.S.Intel LGA 1151 (Z370):Intel Core i5-8600K, Core i5-8400MSI Z370 Gaming Pro Carbon AC4x 8GB G.Skill RipJaws V DDR4-3200 @ 2666 and 3200 AMD Socket AM4 AMD Ryzen 5 1500X, Ryzen 5 1600X, Ryzen 5 1400MSI X370 Xpower Gaming Titanium2x 8GB G.Skill RipJaws V DDR4-3200 @ 2667 and 3200 Intel LGA 1151 (Z270)Intel Core i5-7600K, Core i5-7400 MSI Z270 Gaming M72x 8GB G.Skill RipJaws V DDR4-3200 @ 2666 and 3200 All EVGA GeForce GTX 1080 FE 1TB Samsung PM863 SilverStone ST1500-TI, 1500W Windows 10 Creators Update Version 1703
CoolingGermanyAlphacool Eiszeit 2000 ChillerAlphacool Eisblock XPXThermal Grizzly Kryonaut (For Cooler Switch)
MonitorEizo EV3237-BK
PC CaseLian Li PC-T70 with Extension Kit and Mods Configurations: Open Benchtable, Closed Case
Power Consumption MeasurementContact-free DC Measurement at PCIe Slot (Using a Riser Card) Contact-free DC Measurement at External Auxiliary Power Supply Cable Direct Voltage Measurement at Power Supply 2x Rohde & Schwarz HMO 3054, 500 MHz Digital Multi-Channel Oscilloscope with Storage Function4x Rohde & Schwarz HZO50 Current Probe (1mA - 30A, 100 kHz, DC) 4x Rohde & Schwarz HZ355 (10:1 Probes, 500 MHz) 1x Rohde & Schwarz HMC 8012 Digital Multimeter with Storage Function
Thermal Measurement1x Optris PI640 80 Hz Infrared Camera + PI Connect Real-Time Infrared Monitoring and Recording
Acoustic MeasurementNTI Audio M2211 (with Calibration File, Low Cut at 50Hz) Steinberg UR12 (with Phantom Power for Microphones)Creative X7, Smaart v.7 Custom-Made Proprietary Measurement Chamber, 3.5 x 1.8 x 2.2m (L x D x H) Perpendicular to Center of Noise Source(s), Measurement Distance of 50cm Noise Level in dB(A) (Slow), Real-time Frequency Analyzer (RTA) Graphical Frequency Spectrum of Noise


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Paul Alcorn

Paul Alcorn is the Deputy Managing Editor for Tom's Hardware US. He writes news and reviews on CPUs, storage and enterprise hardware.