What does it report for the ROM and RAM tests? (Or are you not seeing them at all, just what's shown?)
You might want to pull and manually test all ROMs, and either pop two new 6116 RAM in the board, and/or try the RAM that are on there in another known-working board that uses 6116's. And test the CPU in something else as well.
Also, if the board has the original AVG chip, order a repro replacement. They should be changed on all of these. It could be as simple as that.
And you do NOT want to be operating that board into a real monitor, if it's acting like that. You can easily damage the monitor. You want to be using a scope as a display, until you can get it to boot and play blind. Or at least get it to play blind, then use a DMM to test the XY outputs from the video section. Non-booting boards can output excessive XY signals to the monitor that can fry the entire video section in seconds.
Just a heads up. You want to unplug that monitor, and not plug it back in until you've repaired the board, and tested the XY outputs to know they are good. See my 6100 bring-up guide for how to test the XY outputs:
How to bring up a 6100 color vector monitor (A PDF guide) Hi all, I've seen a number of folks with questions lately about bringing up 6100 monitors. On that topic, I have a set of notes that I'd been compiling and adding to over time, with info I've learned (sometimes the hard way) from...
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