IBM Interleaves Core Memory for 360-91.

Built to compete with Seymour Cray's CDC 6600 supercomputer, the IBM 360 Model 91 was the fastest computer available in 1968.  It uses 5 execution units with interleaved core memory like the module below.  The first one delivered to the Goddard Flight Center helped land men on the moon.

YMF - 2196704 

16-way interleaved memory type from 360 Model 91

"The main memory is organized into 16 interleaved elements, so that the CPU may start a memory cycle with a different element every 60 nanoseconds instead of waiting the full 780 nanoseconds. This means that the CPU will rarely get a "busy signal" from the memory, and few machine cycles are wasted waiting for data." - IBM Archives. 

Bottom of the module is stackable

Another YMF - 2196704 8K Density board can be seen at the Computer History Museum in CA.

Red cores from another plane

It just missed fitting in a 9.7" iPad box!