From: utzoo!decvax!decwrl!sun!megatest!fortune!norskog Newsgroups: net.micro Title: Re: 5 mitzie Lisa - (nf) Article-I.D.: fortune.774 Posted: Sun Feb 6 16:04:18 1983 Received: Tue Feb 8 04:01:14 1983 #N:fortune:6400008:000:769 fortune!norskog Feb 6 14:12:00 1983 I would bet that the Lisa uses a 5 mhz clock for precisely the same reason that Fortune uses a 5.5 mhz clock: at this speed you can get lots of cheap, multiply sourced support chips designed for the 8-bit market. When you consider these three factoids: 1) the 68000 uses 95-99% of all available memory cylces, 2) systems of this size are disk-bound, and the Lisa Winchester is a joke, speed-wise, and 3) the 68000 at 5 mhz is somewhere between 1/5 and 1/3 of a vax 780 at raw hardware speed. (The compiled C of a certain company's C compiler runs >half< as fast as Un*x Vax compiled C.) you realize that there is no real shame associated with running a 68K at "only" 5 mhz for a single-user workstation. Lance Norskog Fortune Systems