Some time ago I indulged myself in this: https://forums.tomshardware.com/thr...g-from-m-2-nvme-to-sata-ssd-any-more.3685533/
Long story short: I have and M.2 NVMe drive with Windows 10 on it - and the very same [but slightly older and inactive] OS on an SSD which is connected to the motherboard all the time. It serves as backup system ready to be use at a moment notice, without the necessity of taking out the main OS drive
However: despite taking a lot of time [in conjunction with these tests https://forums.tomshardware.com/threads/ssd-sata-vs-ssd-usb-test-results.3721018/#post-22435297 ] I was unable to force my PC to boot from that SSD when it was connected via USB. I also went through all options available in my BIOS [version F30 on Gigabyte X570 Aorus Ultra rev. 1.2] but found nothing relating to this issue / USB boot settings, aside from the boot order [which was not a remedy]. I tried various slots on he mobo and various USB hardware connections methods but always failed - but the moment I connected that very same drive through SATA cable, the system was able to boot up from it once again
And so: how do I boot from USB SSD?
Long story short: I have and M.2 NVMe drive with Windows 10 on it - and the very same [but slightly older and inactive] OS on an SSD which is connected to the motherboard all the time. It serves as backup system ready to be use at a moment notice, without the necessity of taking out the main OS drive
However: despite taking a lot of time [in conjunction with these tests https://forums.tomshardware.com/threads/ssd-sata-vs-ssd-usb-test-results.3721018/#post-22435297 ] I was unable to force my PC to boot from that SSD when it was connected via USB. I also went through all options available in my BIOS [version F30 on Gigabyte X570 Aorus Ultra rev. 1.2] but found nothing relating to this issue / USB boot settings, aside from the boot order [which was not a remedy]. I tried various slots on he mobo and various USB hardware connections methods but always failed - but the moment I connected that very same drive through SATA cable, the system was able to boot up from it once again
And so: how do I boot from USB SSD?