CDC 7600 12 bit core module
This core memory gives an idea of the increase in density compared with the 6600 for the Small Core Memory (SCM) of 64K words… or 1/2 the size of the 6600. This is totally counter-intuitive to what we would expect. However, the speed was accomplished by the operation with the LCM. Access time for the SCM was 4 clock cycles and cycle time, 10 clocks.
Thirty-two overlapping memories had an aggregate bandwith of 36 x 32 or 1152 Mwords per second for a computer that operated at 36 Mega-ops.
The Large Core Memory required 64 clock cycles, so transfers between LCM and SCM occurred in packets of 8 words to more closely match the performance of the SCM.