I have an AGS Orion cabinet that has a 6607 in it, the bill validator comes online but won't accept any bills, spits them back out.  Does anyone know what it uses for config (like bally or something else).

Okay...I can see it now....thanks shortrackskater!
It's kind of referring a problem with a CPU/MPU RAM stick on the "2nd block".
There's possibly a couple of RAM ( Random Access Memory) sticks...the 2nd one might have some corrosion on it's contacts.

With the power OFF, go inside and look onto your main circuit board for the machine.
There will be a computer memory stick or two.
Kind of like the kind they used to have in desktop personal computer towers back in the year 2000's.
Pop them out, you may have to look small release clips on each end of the sockets.
Note how they come out...they only go back in one direction into the sockets.
Rub the gold contacts on the memory sticks with a white eraser - that'll help clean them a little to give them better contact with the socket contacts.
Then re-install them back into their respective sockets and turn ON the power switch and boot up your machine.

Also, check the voltage of the onboard coin cell battery.
Although I suspect it may be okay because at least some messages came up, they may be too low.
That'll cause boot up problems and black LCD screens.
The machine just won't work right.

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