How to fix voltage instability on ASRock Z370M Pro4 for Once Human?
Exploring open-world bases was a nightmare; the screen would just hitch violently without warning, making the controls feel sluggish and unresponsive. I noticed the VRM on my ASRock Z370M Pro4 was hitting 82-88℃ under sustained load, causing the CPU core voltage to bounce wildly between 1.15V and 1.28V. At first, I tried enabling High Performance mode in Windows, but that just made the voltage swings more frequent—a total waste of time that left me completely baffled. I eventually dove into the BIOS Advanced Voltage settings and switched the Load-Line Calibration from Auto to Manual, locking the CPU core voltage at 1.22V. Checking HWiNFO, the voltage ripple immediately tightened to within 0.02V, and frame times dropped from a chaotic 12-45ms to a consistent 14-18ms. I did run into two random reboots right after the first lock, but tweaking the VCCIO to 1.1V finally nailed it. Now, the VRM stays around 72-76℃ with fans humming at 1800-2100 RPM. The voltage waveform is basically a flat line now, and the game finally feels smooth.
