GEC 4070

The 4070 was introduced as a poor man's version of the 4082. Core store was slow, and to gain performance, the 4080/4082 could interleave store accesses, i.e. it could perform simultaneous access to multiple store locations. The 4070 had the store interleaving switched off. It was sold at a lower price, and later the customer could pay for an upgrade to a 4082 to gain performance. The 4070 could support 512kb of core store (this was probably a marketing limitation, the technical limitation almost certainly being 1Mb like the 4082).