Need assistance with the I7 6700K and Gigabyte GA-Z170XP-SLI ATX?
Need assistance with the I7 6700K and Gigabyte GA-Z170XP-SLI ATX?
Philipew explains how to handle voltage variations. He notes that minor fluctuations are normal and suggests adjusting an offset voltage to maintain stability. He describes the process based on his own setup and observations, emphasizing the importance of managing current and voltage relationships for power consistency.
Keep in mind the core voltage. If it only slightly exceeds the value you have configured, that’s typical. My setting is 1.420, but when under load it rises to 1.432. To balance this, you should apply an offset voltage. With my unit, the difference is 12mV, so using -0.012v would maintain a stable 1.42 instead of 1.432. In your diagram, the increase is noted, which means the offset should match what I have. It’s unusual that voltage decreases when load increases—it acts as a protective feature because current rises under load and power equals current times voltage. When voltage falls during load, it’s called VDroop. Greater current through the 12V rail causes a lower voltage. I believe it can drop to around 11.5V before it becomes out of spec. To handle this, the BIOS usually includes a setting named vdroop. The current supplied by the 12V supply is controlled via PWM phase control, aiming for consistency (high quality). Voltage swings should stay within a few thousandths of a volt, which is why a premium PSU is recommended, especially as temperature and current rise. My Gigabyte GA-Z170XP-SLI features three drivers for the phase rails, two more for VCC, and additional ones for the iGPU. A single Hybrid-Digital PWM provides the 4+3 phase output for VCC (VCore) and VCCGT (iGPU voltage). The precise voltage from the phases is accurate to the thousandth of a volt, ranging between 1 and 2 volts (Intel set a "safe" limit at 1.520V for 6600K VCore). VCCSA and VCCIO come from a linear regulator optimized for low power needs. They also operate between 1 and 2 volts (1.250V on Auto). The phase current can reach up to 20A. Higher switching rates improve current smoothness but raise VRM temperature, affecting stability over time. A quality PSU is essential to maintain a stable voltage despite these changes. Considering VDroop, at 4.6 GHz my CPU VCore voltage—set in BIOS at 1.355V—fluctuates between 1.332V (under load) and 1.356V (idle), or two 12mV steps, which may lead to instability—meaning it drops from its set value to around 1.332V when under load and rises to 1.356V when idle. With LLC (Load Line Calibration), VDroop is reduced, dropping VCore to 1.344V under load from 1.356V idle, or a single 12mV step, resulting in much better stability (Prime95 29.8 v2). This shows it falls from its set value to about 1.344V when under load and rises to 1.356V at idle. Compared to what you mentioned:
"I have mine set at 1.420 but the voltage goes up to 1.432 under load."
...in my case:
"I have mine set at 1.355 but the voltage goes up to 1.356 AT IDLE"
...which is different—this is not under load."
Ignore VID. You should focus on Core Voltage. A slight rise beyond the set value is normal. I adjusted mine to 1.420, but under load it reached 1.432. To fix this, apply an offset voltage. With a 12mV increase, the offset should match what I have—-0.012v—to maintain the voltage at 1.42 instead of 1.432. In your diagram, you observed a similar 12mV change, so the offset would be consistent with mine. Did you use an offset voltage or adaptive + offset? Thank you.