Well, actually, IBM released the first 370 in 1968, only they didn't want to tell anybody too soon. So, they camouflaged it as a new 360 model, the /85, and only sold it to the (US) NSA, so nobody was going to get to see it for a while. The 360/85 was a prototype of the 370/165, and they really didn't change much to make it the 370. The /85 had 16-bit static RAM for a small writable control store and storage buffer (cache), as well as a read-only control store for the 360 instruction set. The 370/168 moved up to 64-bit static RAM chips, and the entire control store was writable. They also changed the logic cabinet layout a bit. The computer console was identical, as far as I can tell, although photos of the /85 are extremely rare. The /85 was the first machine IBM delivered with the MST4 monolithic logic chips, storage buffer, writable control store, water cooling, and probably a few other things. Jon