Can you post your BIOS configuration?
(Thanks to
@Zip1 for helping put this together!)
Press F2 to toggle to Advanced Mode.
Press F7 to Load Optimized Defaults.
Now make the following settings:
Tweaker
Advanced CPU Settings → VT-d → Disabled
Extreme Memory Profile (X.M.P.) → Profile 1
Settings
Internal Graphics → Enabled
Above 4G Decoding → Enabled
Thunderbolt(TM) Configuration
Security Level → No Security
This will trigger a 'Save & Exit' dialog so press ESC to close the dialog.
Discrete Thunderbolt(TM) Configuration
Thunderbolt USB Support → Enabled
GPIO3 Force Pwr → Enabled
USB Configuration
XHCI Handoff → Enabled
Boot
Windows 8/10 Features → Other OS
CSM Support → Disabled
Some devices such as GPUs may require CSM Support to be enabled. There is no harm in setting this to either Enabled or Disabled. Use the setting that works best.
Save & Exit → Save Profiles → Save to Profile 1
This preserves the firmware settings for easy recovery.
My current version number is F9b, and of course F6 is another configuration.I got it according to this, on the first page.