Forget CPU and GPU thermal throttling — charge rate throttling is now a thing.
- The charging circuit doesn’t have enough cooling and tends to overheat.
- Since the charging circuit and the CPU use the same heatsink, the heatsink already warmed by the CPU does not have a low enough temperature to efficiently cool the charging circuit.
- The charging rate is temperature-dependent, but the charging circuit doesn’t seem to have a temperature sensor, so Huawei probably went super conservative about protecting the charging circuit and modeled its temperature after the CPU temperature.
Therefore, even when the CPU is a little bit warm, the charging rate thermal-throttles.
I will discuss solutions to reduce this as part my throttling elimination project.
Also, the recent BIOS updates seem to have slightly improved the charge rate.