Vector Workstation Display Issues - quad a5000, no display output post grub, no recovery

I have a quad a5000. The machine went unresponsive over the weekend, and doesn’t generally want to output to the display.

I followed the procedure to clear CMOS and flipped the VGA switch to disable (per instruction from support).

I can get it to boot to bios, I can get display the grub boot screen, once I select (or let it timeout and choose) ubuntu, the screen blanks and never returns.

If I try to boot the recovery image from USB, it loads to grub, once I select install, the screen goes black, never to return again

The motherboard indicator reads AA.

I am using display port (the only option on all 4 port on each card), and I am currently in the topmost card, in the port closest to the glass (farthest right if viewing from the back).

I have tried all the other ports, it makes no difference.

Any ideas? I am literally at a standstill, and badly need this thing running experiments, nowishly.