Dual-boot win/linux with UEFI bios mode

[Nicolas25]

Hi

I tried to install ubuntu as a second OS on my notbook HP Splitx2  but the Grub nor the default UEFI bios start can start ubuntu after this install.

The normal way, win8.1 start normally.

When I intercept the boot with F9, I can see 2 choices, Windows or Ubuntu. But the Ubuntu doesn't work and still goes ( I suppose ) to the old install :

Currently I have windows on SDA1 (internal hard disk) and try to install ubuntu on the microSD card (internal card readed) on /dev/mmcblk0 as show in this boot-info resume: https://paste.ubuntu.com/p/RYvcHMGQsz/ 

I previously made both windows and ubuntu installed on the same SDA1/ but this 64Go hard disk was to small for supporting both OS, that's why I installed ubuntu on a second drive, the microSD. But it seems like if the bios UEFI didn't care about the change, and I don't know how to manage this ?

Finaly, when I select Ubuntu choice after F9 bios UEFI menu, I fall in a old Grub command line (not DOS nor Linux command line, just Grub) and I don't know what to do with that.  Can you help me please ?

According some ubuntu experts ( I asked in https://forum.ubuntu-fr.org/viewtopic.php?pid=22255069#p22255069 french forum ) it seems the boot-info is correct, and the ubuntu install finished successfully anyway. that's why my last hope now is to configure the bios with the second bootable partition !

[Lil_Boy_Blue]

Hi

Some guides....
https://ubuntu.com/tutorials/tutorial-install-ubuntu-desktop#1-overview
https://itsfoss.com/install-ubuntu/
https://www.cnet.com/how-to/how-to-install-linux/
https://www.wikihow.com/Install-Ubuntu-Linux

I assume you are using Secure Boot

and if GRuB has installed and detected W10 and is the second Boot Manager (Microsoft being first, Ubuntu being later in the alphabet) then change the order/sequence so that OpenSuse Ubuntu Secure Boot is first.