Ok I found out a bit of info. Did you disable VT-d in bios? If not you need slide=0 I think.
@Leesureone will chime in with the answer I'm sure.
slide=0 is for boot.efi so it may be used only with Clover. More reading has dart=0 as the boot aug that disables VT-d so I'm not sure. Anyway check Bios settings might be the answer to why slide=0 is needed for you.
Now then it goes on to say to eliminate the need for slide=0 you disable vt-d in bios
Now I do have this disabled in my bios do you? I realised Rehabman doesn't mention this bios setting but I used Cric's NUC guide for bios settings as well and he DOES say to turn it off.
Search BIOS SETTINGS
See
https://www.tonymacx86.com/threads/...2-on-intel-nuci5beh-using-clover-uefi.268502/
Cric uses Rehabman's guide and his bios settings are below:
In order to boot the Clover from the USB, you should visit your BIOS settings:
- « Inter VT for directed I/VO (VT-d) » should be disabled
- « Secure Boot » should be disabled
- « Legacy Boot » should be enabled
- « Fast Boot » should be disabled
- Boot->Boot Devices-> « USB » should be enabled
- SATA mode should be AHCI
- Boot->Boot Configuration-> « Boot Network Devices Last » should be disabled
- Power->Secondary Power Settings, « Wake on LAN from S4/S5 », set to « Stay Off »
Take a look at your bios and get back to me.