Realistically, think about the timeline on these products, introduced in 1990. To back up design and cert efforts those had to start in the mid/late 1980’s. Thus the chipset tech had to be selected in the late 1980’s. Now frozen in time from a cert perspective. What was commerically available then?
30386 CPU tech running at 32 MHz, which per the maintenance manual says the CPU runs at. When was the last time you tried to find 30386 computer parts from nearly 40 years ago? What chipset manufacturer keeps 40 year old chip foundry equipment?