Debian Stretch on The Optiplex 755

Installed on the mighty Optiplex 755 past Friday, as part of the Debian Everywhere directive :p
As usual with the Optiplex, I'm using the old Apple Cinema Display monitor, with the ADC to DVI adapter.
Installation went fine, as usual, and usual, went the path of an encrypted LVM.
Everything works Ok on Debian, but, as it happened with every single distro I've used with this monitor/ adapter combination, some of the booting messages/ screens aren't displayed.
For instance, on Debian, you can see GRUB's kernel menu, but the LVM pass-phrase screen doesn't show up.
But, that is just for the booting, once the whole system is up and running, everything works A Ok, proper resolution, sound, etc, etc.
And of course, the system goes (and comes back from) Suspend without any error or problems.