If I am reading this correctly. Its also now running loud with the HD back in. Which begs the question the heat dissipation of the removed heatsink fan is now as good as before. I know OEM's and Intel us some silver product which is very thin and NOT the while silicone heatsink grease of the olden days
Its not clear if it was running normally under Windows 10 on the HD.
BIOS settings should have the master control and be coded as such with some performance cooling options as some desktop motherboards do. We should not rely on a Power Manger to handle cooling. That would make many systems near obsolete if they cannot be upgraded to the next OS that comes along. I have already run into that in two of my HP notebooks because they are Nvidia exclusive and Nvidia is not longer creating driver for that chipset. It appears the same will happen with many systems sold by Lenovo once support is stopped for a chipset. The next OS after Windows 10 will no likely work.