My old Inspiron 11 got its display broken and I decided it could be used as a desktop simply by removing the display. I stripped everything out and I got only the box with the keyboard and the mousepad but I decided to keep the internal display plugged just to see everything was working and indeed, the BIOS loaded nicely and consistently booted up using an USB with Ubuntu. I then connected it to a monitor from HDMI included in the laptop, unplug the internal display and power the computer again. For my surprise, this time the BIOS didn't finish loading and kinda freeze (it allowed me to press F2 for setup but never reached it). Out of curiosity, I plugged again the internal display and this time the BIOS loaded without any issue.
I'd find strange that the BIOS would be locked by failing to contact the display. Does anyone knows if that's the case? How can I boot the machine without connecting the internal display?
I hope I can find help here.