The one on the right is gold cap chip board I can’t be sure with the top side bi based on the PTH layout the middle one is telco and the left is peripheral. Mind you if the ICs aren’t actually installed in the the through holes that would not hold up Grade wise. Middle one has many DIP grids, and two PGA grids. Guessing an analogue and a digital effects processor in the latter.
Keeping DIP (dual inline pin, or rectangle) chips in the sockets on telco boards is normally a must. However given the age you may want to temporarily pop them out to check the legs. Many of the various controller chips can have gold legs: when the IC is ceramic it usually places them in the Pentium/Mac ceramic class. A few of those are worth taking the board downgrade to peripheral as the price difference is is huge.
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