1. Windows update sometimes overwrite drivers, especially when its new build update. E.g latest 1803. Always double check your device manager.

2. Disable Hyper-V

3. Disable core isolation under new setting for Windows security.

4. Enable virtualization through BIOS setting

My choices for android emu are Nox and Memu. Although there is a newer one in town, LDPlayer which loads 5.1 by default like Memu, i still prefer Nox

App crashes a lot in their beta 7.1.1, which causes android system to reboot.

Currently using 6.2.3.9 which was updated few days ago, so far so good. They have changed their default android version from 5.1.1 from 4.4.2.
Both 4.4.2 and 7.1.1 still downloadable from Nox Multidrive manager. So far good performance at 5.1.1, better than Memu.