HP elitebook x360 1040 G5 Stuck at 'Entering setup menu...'

[B83C]

Received a faulty HP elitebook from my friend that does not boot up properly. The internal display is broken, so the only way to view the display output is via hdmi. However, when booted up the screen get stuck with 'Entering setup menu...' when esc is pressed upon booting. HP logo isn't displayed on bootup, only black screen, but an underscore cursor appear on top left corner of the screen. Has anyone any idea what could be the culprit here? I have flashed both the EC and BIOS flash but to no avail. The serial number is 5CG9377GCT, and below is the original flash content:

Also the fans spin at max speed on bootup, is that normal?

[mcplslg123]

Disconnect all peripherals like keyboard/hard disk etc and see if it makes any difference.

[B83C]

Harddisk hasn't been connected at all, and only the internal keyboard is connected, which should not cause any issues

Edit: I tried disconnecting the internal keyboard, obviously didn't work