i setting new linux-only system, supermicro motherboard x10srl-f, xeon chip, , geforce 1070 gpu. hardrives set legacy (not uefi), secure boot disabled, though csm still enabled. ubuntu install works fine, , switched processor intel proprietary drivers , installed intel gpu tools , rebooted, no problems. ran sudo apt-get update, reboot, no problems. however, have tried both switching nvidia driver 367 in system settings , running sudo apt-get install nvidia-current (which should driver 367), , both lead login loop on reboot. have tried install driver 361, same issue. i have tried suggested here: ubuntu gets stuck in login loop , permissions not problem, have uninstalled , reinstalled lightdm, again no help. believe have tried can find @ point, appreciated. edit: have run sudo apt-get purge nvidia* , reinstalled, fresh install of ubuntu 16.04, did not edit: have tried switching gdm3 (different error), caused different error, did not resolve issue. also, running sudo apt-get i...