Hello,
For the record, I'm facing the very same problem of installing Debian 9.5 (I tried 8.11 too) on a beelink X55 and VBook A1 celeron.
I tried rufus, unetbootin, etcher, dd, cp, 2 different usb dongles but the results are the same on both PC.
Secure boot and fast boot are disabled.
I can select the USB dongle in the UEFI boot menu (after the hardware manufacturer splash screen) and as soon as I press enter, I get a black screen with a non-blinking white cursor on the top left corner. I can't access grub menu.
Sceenshots here
http://www.bee-link.com/forum.php/forum ... a=page%3D1
On the other hand, I managed to install Ubuntu server 18.04 and Centos 7, on both pc.
There is definitely something fishy with the debian iso.
BR