>>62
CSM切ったときにBIOSで動き遅くなるのは既知のバグ。
CTRL-F6で解像度下げれば良い。

Disabling CSM causes BIOS to become slow : Reproducible / Working on a fix*

*Temporary work around on latest BETA (F7B) - Press CTRL-F6 in BIOS. Set resolution to "VGA First" This will lower resolution but should fix the lag. Its just a temporary work around. Let me know if if works.