Consistent with your situation, if you don't press F8 to disable the driver's mandatory signature, you will keep turning, and it is useless to press other buttons. The two operations mentioned in your topic are also useless. F8 After the forced signature of the driver is disabled, it can be started normally. After booting up, I checked the unsigned driver and found that there are two basicrender.sys bthport.sys, the first one is the basic render driver. I suspect that this driver is broken, but uninstalling and reloading my graphics card driver can't repair this driver. Moreover, this basicrender.sys was copied from the newly installed system, and it is invalid to replace it in PE. At present, I have no good way, only to reinstall the system, or to find a way to guide the default option of disabling driver mandatory signature, but I can't find it, because the method on Baidu is the same as your topic, which is really painful. The point is, I can't even get into safe mode.