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Test Setup & Overclocking
Test Systems
We're using MSI's X299 Gaming Pro Carbon AC for testing. We disabled the all-core Turbo Boost feature to ensure a level playing field.
Skylake-X processors can scale beyond DDR-4000, but we settled on DDR4-3200 for our overclocked config to match the transfer rates of AMD's overclocked Ryzen CPUs.
In the U.S. lab, we attained a 4.6 GHz overclock at 1.28V. This proved stable for 12 hours under AIDA's FPU, cache, and CPU tests. Temperatures hovered ~85°C during the non-AVX load. We were also able to run Prime95 for extended periods, but the processor frequently engaged in aggressive throttling due to thermal constraints. As such, we used an AVX offset to lower the clock rate during AVX-enabled workloads.
Trying to push beyond 4.6 GHz required excessive voltage, which in turn generated even more heat. That's no good with Skylake-X, so we stuck with the safer, more stable settings. Budget in a closed-loop liquid cooler at the very least to keep Core i7-7820X from throttling at stock frequencies. More aggressive overclocking begs for a custom open loop.
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.
The only updated components in our German lab are the CPU, system memory, motherboard, and new cooling solution, so we'll just provide a quick overview in the following table:
| Test Equipment & Environment | |
| System | Germany Intel LGA 2066Intel Core i9-7900X, i7-7740XCore i5-7640X, Core i7-7820XMSI X299 Gaming Pro Carbon AC4x 4GB G.Skill Ripjaws 4 DDR4-2600AMD Socket AM4AMD Ryzen 7 1800X, 1700X, 1600X, 1500XMSI X370 Tomahawk2x 8GB G.Skill Ripjaws V DDR4-3200Intel LGA 2011v3Intel Core i7-6900KMSI X99S XPower Gaming Titanium4x 4GB Crucial Ballistix DDR4-2400Intel LGA 1151Intel Core i7-7700K, i5-7600KMSI Z270 Gaming 72x 8GB Corsair Vengeance DDR4-3200 @2400 MT/sAll 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 Supply Unit (PSU)Windows 10 Pro (All Updates)Be Quiet Dark Power Pro 11, 850W Power Supply Unit (PSU)Windows 10 Pro (Creators Update)U.S.Intel LGA 2066Intel Core i9-7900X, Core i7-7820XMSI X299 Gaming Pro Carbon AC4x 8GB Corsair Vengeance DDR4-2666 @ 2666 and 3200 MT/sIntel LGA 2011v3Intel Core i7-6900KASRock X99 Extreme44x 8GB Corsair Vengeance DDR4-2666 @ 2666 and 3200 MT/sAMD Socket AM4 AMD Ryzen 7 1800X, 5 1600XMSI X370 Xpower Gaming Titanium 2x G.Skill FlareX DDR4-3200 @ 2666 (stock), and 3200 MT/s Intel LGA 1151 Intel Core i7-7700K MSI Z270 Gaming M7 2x G.Skill FlareX DDR4-3200 @ 2400 All EVGA GeForce GTX 1080 FE 1TB Samsung PM863 SilverStone ST1500, 1500W Windows 10 Creators Update Version 1703 |
| Cooling | GermanyAlphacool Eiszeit 2000 ChillerAlphacool Eisblock XPXThermal Grizzly Kryonaut (For Cooler Switch)USCorsair H115iCorsair H100i v2Arctic MX4 |
| Monitor | Eizo EV3237-BK (Workstation, Office, HPC) |
| Power Consumption Measurement | Contact-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, 500MHz Digital Multi-Channel Oscilloscope with Storage Function4x Rohde & Schwarz HZO50 Current Probe (1mA - 30A, 100kHz, DC) 4x Rohde & Schwarz HZ355 (10:1 Probes, 500MHz) 1x Rohde & Schwarz HMC 8012 Digital Multimeter with Storage Function |
| Thermal Measurement | 1x Optris PI640 80Hz Infrared Camera + PI Connect Real-Time Infrared Monitoring and Recording |
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