EV is the prefix used by
the company formerly known as DEC to describe one of their
Alpha CPU cores. The breakdown for the EV cores is as follows:
EV4 : 21064
EV45 : 21066a
EV5 : 21164
EV56 : 21164a
EV6 : 21264
EV7 : 21364
EV, a reference to the famous DEC Tech Report at:
http://www.research.digital.com/wrl/techreports/html/TN-13/ , stands for Electro-Vlasic.