Still haven't found a solution or a workaround. What I've found till now is:
* All daily testing debian installers (besides debian 8, debian 9 and debian buster alpha 3 installers), up to October 15th, produce exactly the same result. * Adding the option fb=false to the kernel options results in the ten miniscreens (see image in previous message) just not appearing: I'm left only with the grub background. * All other option changes I've tried, either in grub, kernel or BIOS didn't have any effect. For grub this includes: set gfxpayload=keep, set gfxmode=1024x768 (several values) and terminal_output gfxterm. For the kernel: vga=normal, vga=several modes, video=several modes, text, nofb, nomodeset, intel_pstate=no_hwp, intel_pstate=disable, intel_idle.cmax_cstate=0, i915.modeset=0 and a few more. For the Fujitsu Celsius w580power+ BIOS, I've tried changing most of the options for Graphics, tried reducing the number of active CPU cores, disabled hyperthreading, and changed lots of boot related options. * Changing the graphics card, the output port of the graphics card, or the monitor (different resolution and aspect) didn't have any effect either. * Installing Debian in another computer and moving the installed disk to the Fujitsu, results in a blank screen on boot. I suspect the system went to the initrd shell on attempting to boot, since I couldn't get a network connection but there was some response to the keyboard. * Linux Mint 18 fails too in this computer (blank screen instead of ten miniscreens). Mint version 19 does work. * Ubuntu 18.04, Server and Live/Desktop, work. Ubuntu 16.04 doesn't (blank screen). Ubuntu 18.04 network installer has exactly the same problem as Debian (not surprising, since it seems to use some variation of the Debian Installer too). Hope some of this gives some insight into the problem.
