IBM CISC processor

[isa-d]

I get this processor board from an AS/400 9404 E10
it has a CISC processor but which is between these 3 chips?
it has 2 crystals (30.77000 MHz and 22.118440 MHz) and the slopes seem connect them with the chip at right in the first picture
what do you think, is it the processor?

[UMMR]

Hello,
AFAIK the IBM AS/400 CISC processors aren't single-chip CPUs.
Paolo

[isa-d]

[doccybrown]

An for us currently nameless 48bit-processor and indirect
predecessor of 64bit RISCs Cobra and Muskie
(which were anon predecessors of the RS64).
The architecture was optimized for data serving so likely alot
of cache-memory and separated memory- and bus-controllers,
no FPU at all I think. There could be already first steps in pipelining.
Just less silvercans like in IBMs S/38 which was the forerunner of AS/400-systems.
On your board one of the silvercans is probably
an integer execution unit (like IBMlers are used to say) and
could be called CPU. In small S/38's the "processor" is two small
boards with more than ten silvercans if I remember correctly.
Question here is if ALUs and control, decode, registers... are sitting in
the same package, considering the mass of silvercans likely not.