Here is a report about the use of early-mid 1970s 4k x 1 DRAMs in the Apple-1.
Most of us are using later 4k x 1 DRAMs produce towards the end of the 1970s or later, such as the ones I furnished with my famous kits (now sold out). Typical examples are:
Motorola MCM4027AC3 Date codes 7927, ...
Mostek MK4027N-4 Date codes 7935, ...
Intersil MK4027J-3 Date codes 7948,8017 ...
It was found that the former needed all the "reliability mods" with the extra bypass capacitors and the six damping resistors, Mostek often was happy with only the damping resistors, and on some PCBs / builds, the Intersil ones needed no reliability mods at all…
