Did you read Matthew Garret's blog post, linked upthread and referenced in my comment, that claims Microsoft (allegedly) ships a faulty AHCI driver loaded by default with Windows 10 that (allegedly) causes a drop in system efficiency which (allegedly) harms battery life, and that Lenovo (not allegedly 'cos we know they did this bit) blocked off AHCI in the BIOS in order to (allegedly) force Windows to ignore the faulty AHCI driver and load the RAID driver instead? That would be Microsoft's fault, no? Except here we're talking about a BIOS that only has a RAID option and nothing else. Y'know, because of the BIOS block. That is most certainly not common.