CPU: Intel Core i7-7700K
Motherboard: Asus ROG Maximus Code
RAM: 32GB Kingston HyperX 3200Mhz
SSDs: Kingston KC1000 480GB
Chassis: Corsair Spec-04 Carbide Series
EVGA 74.83 CFM Fans Extra Testing
OS: Windows 10 Professional X64
We pondered what software to use for stressing the CPU 100% and OCCT and Prime 95, as well as Intel Burn, just produce an unrealistic amount of heat. Some of the CPU stress programs are designed specifically to generate heat which has no real bearing on real-life computing. We tested a host of software from Realbench to never heard of programs and finally landed on CPU-Z and the Stress CPU utility. It's easy, free and available to everyone and during test selection; it consistently kept 4 cores 8 threads at 100% and generated enough heat to convince us of the validity of the Stress Test.
Notice the Stress CPU Button, we used 4 Core 8 Thread testing
We went with a worst case scenario, no chassis fans, no ambient air movement. Lab temperature was kept at 72oF or 22oC throughout testing. We disabled Intel's Turbo feature and locked the CPU to a steady frequency and CPU voltage for each clock speed on the CPU. We went into BIOS and set OC profiles for 4.5GHz, 4.6GHz, 4.7GHz, 4.8GHz. We cut off at 4.9GHz as the CPU voltage required to reach 5GHz stable with a stress test load running for an hour were just unacceptable and liable to degrade the CPU. To sustain a 5GHz OC we were well over 1.42v and Asus recommends triple radiator cooling for 1.35v (which we exceeded). We fired up the test station and let it Idle for 30 minutes and recorded the idle reading. We then ran the test at each CPU speed for an hour then recorded the reading.
Between tests, we shut the machine down for 30 minutes then went to the next CPU speed. Each test at each speed was repeated 3 times then we report the average of the 3 readings. Every test was run using the pre-set profile in BIOS without any changes to maintain test consistency.
We used the provided thermal material on the Cryorig cooler for testing. We did each test with Arctic Ceramique and the readings didn't change so use the included paste if you want it's pretty good. Thermal measurements were taken using RealTemp.