i've had those crashes too. Mostly black or green screens. At times i was able to minimize the game and get graphics running again (playing Path of exile).
Even the Browser sometimes managed to crash my System. I guess you're not alone with the issue.
A new thing i've tried today was to install a newer Bios (UEFI) Update and graphic drivers released by Asus wiht a raven APU hotfix patch. But those drivers aren't the newest version to start with (23.20.817.0).
"AMD Graphics Driver
AMD Graphics Driver V23.20.817.0(AMD package 17.40.3301) for Windows Win10 64bit. (Only support Raven APU，please run “AsusSetup.exe” to install hotfix and Raven Graphics Driver.)"
You can install the new driver available here : Radeon Software Adrenalin Edition Q2 2018 Release Notes
Note : It is essential that you reboot the system after you install these drivers.
Please submit your feedback on any issues with this driver here.