Dear Andrea: I tried disable linux boot, no help, getting worse. I see about 10+ times after seeing "loading kernel, loading initial ramdisk" then computer reboot. Normally if it works after seeing "loading kernel, loading initial ramdisk", the top screen will show a cursor blinking then boot message and soon show gnome desktop. I enabled "linux boot" again. Now still 1 of many retries can go into system, many many retries and finally in. I checked "security boot" disabled. And windows 11 boot quite well, no failures so far.