just after its start to getting hot..Fans go fast from the beggining, or just when CPU (maybe GPU) gets hot?
how do i switch?Battery drain fast in both iGPU and dGPU modes?
no, but you think it can drain the battery becouse of that? maybe it can down the temp 10-20deg but no to much....but i will check..Didn't speciy if you tested with another heatsink...
yes the same..Same happenes if you test with battery alone?
Already tried that..Try installing original macOS, from Internet Recovery (Shift + Command + Option + R).