T460s: Current Limit Throttling / ICCMax

[m0biusace]

Hello all.

Picked up a secondhand T460s. i5-6300u. Windows 10 pro. I have noticed that on battery power when battery 2 (the one that discharges first) goes below 30-40% the CPU is downclocked to 1.4ghz max. Intel XTU says the CPU is "current limit throttling" and the Processor Core IccMax is 5 or 6amps, instead of its usual 25-32A.

If I manually raise the processor Core IccMax to 32A, it resolves the throttling. However a reboot puts it back to 5-6A, making the laptop substantially slower.

Anyone else have a similar issue? I have seen IccMax used on other laptops to throttle but it's usually at the extreme ends of temperature/performance. This just happens when battery 2 is below a certain percentage, even if battery 1 is at 100%. This even occurs when the AC adapter is plugged in.

All temperatures are fine. I have even repasted the CPU to no change. Downgraded BIOS to lowest allowable, installed different lenovo power management drivers. Windows power management is on high/best performance. No change to behavior.

Anyone else have a similar issue?