Intel has restricted direct voltage control for most mobile processors starting from the 12th generation due to the Plundervolt vulnerability. This change makes traditional undervolting via software like ThrottleStop or Intel XTU impossible for most H, P, and U-series chips, leaving these settings as non-functional UI elements.
Users can bypass these restrictions by modifying loadline parameters within the BIOS/UEFI settings of certain motherboards and Mini-PCs. Specifically, adjusting AC Loadline can reduce the voltage requested by the processor under load, while DC Loadline affects how the CPU calculates power consumption and triggers PL1/PL2 limits.
In the case of the fanless Chatreey TK12-F Mini-PC equipped with an Intel Core i5-1235U, the author optimized performance by adjusting power management settings. The configuration was changed to 'Max Non-Turbo Performance' mode, with PL1 set to 15W, PL2 to 40W, and Tau increased to 56 seconds.
These adjustments resulted in a significant increase in single-thread performance in CPU-Z, rising from 475 to 647 points, while multi-thread performance remained stable at 3737 points. The author notes that the heavy, heat-dissipating chassis of the fanless device allows for longer sustained boost periods without overheating.
