[net.micro.apple] MacMemory

alex@sdcsvax.UUCP (Alex Pournelle) (06/12/84)

Has anyone out there actually hot-rodded his Macintosh to 512K?  We're
about to, soon as we find out for sure which jumper to switch.  Any data
on that would be appreciated.

Alex

jalsop@aesat.UUCP (John Alsop) (06/14/84)

I was told last week by local Apple marketing rep. that increasing from
128K to 512K requires a new PAL, as well as memory chips.

Can anyone comment on this?

bourne@siemens.UUCP (Dave Bourne) (06/14/84)

	The PAL chips provide all the address decoding, bus control, timing,
	refresh garbage for the RAM, etc. etc. (see first issue of MacWorld
	or February '84 issue of Byte magazine).  When upgrading from 128K
	to 512K, its probably necessary to decode a few more address lines
	thus requiring a new PAL chip as well as new memory chips.

	Is this the type of comment you were looking for?

			"The buck does NOT stop here"
					dave
				    at
					siemens!bourne