So like any good tale of woe, it all started one day when I was browsing Ebay for Fore ATM gear and I noticed something interesting in a "system controller" for a large ATM switch:

I convinced myself that I had to have it and after some back and forth, I ended up having the board shipped to my house where I quickly liberated the real prize:

This is a Ziatech/Ribbon/Performance Technologies 5520 - compactpci 440FX dual pentium pro board. On the bottom of the board you can see a network mezzanine card, hiding under that is a compact flash board.
Datasheet is available here: https://web.archive.org/web/19970626050439/ht … heet/5520ds.pdf

I was also able to find a copy of the manual:

While the datasheet shows a VGA port, I don't believe the board has any video function without a special VGA mezzanine module (zPM10 or zPM11). I put the board in a chassis and hooked up the serial port and was greeted with angry VXWorks - it complains that it can't find some necessary hardware and then bootloops, which makes sense. There was no BIOS output over the serial port. Pulling the CF card just makes the bootloader angrier:

I imaged the CF card but it is just a VXWorks install. I tried a compactPCI video card, however there is no output (even with keyboard connected). There is a worrisome label on the board:

As a last ditch, I blew away the flash card and installed dos on it with ctty com1 in autoexec.bat, however the boot loader does not want to boot from a dos partition.