Michael Larabel, writing for Phoronix: Intel is planning to end "legacy BIOS" support in their new platforms by 2020 in requiring UEFI Class 3 or higher. Making rounds this weekend is a slide deck from the recent UEFI Plugfest. Brian Richardson of Intel talked about the "last mile" barriers to removing legacy BIOS support from systems. By 2020, they will be supporting no less than UEFI Class 3, which means only UEFI support and no more legacy BIOS or CSM compatibility support mode. But that's not going to force on UEFI Secure Boot unconditionally: Secure Boot enabled is considered UEFI Class 3+. Intel hasn't removed legacy BIOS / CSM support yet due to many customers' software packages still relying upon legacy BIOS, among other reasons. Removing the legacy BIOS support will mitigate some security risks, needs less validation by vendors, allows for supporting more modern technologies, etc.