Just because nobody seems to have mentioned it. . . Without multiplexing, 64 bit addressing of external memory requires 64 external pins on the chip. Have you looked at the pins on a modern processor chip? Where would you put 32 more? How about the printed circuit wiring that connects the memory address lines to the bus while keeping all exactly the same electrical length?
Someone has properly chosen fewer than all 64 bits until we really need those exabytes. (Or are they exibytes?) -- --> As a citizen of the USA if you see a federal outlay expressed in $billion then multiply it by 4 to approximate your share expressed in dollars. <-- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/g3-5-list
