Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!zaphod.mps.ohio-state.edu!mips!news.cs.indiana.edu!bronze!rwyckoff@copper.ucs.indiana.edu
From: rwyckoff@copper.ucs.indiana.edu (richard wyckoff)
Newsgroups: comp.sys.mac.hardware
Subject: 32-bit addressing for RAM
Message-ID: <1991May25.023925.9850@bronze.ucs.indiana.edu>
Date: 25 May 91 02:39:14 GMT
Sender: <rwyckoff@copper.ucs.indiana.edu>
Organization: Indiana University
Lines: 21


Michael Weiss  (weiss@watson.seas.ucla.edu) writes:

>On another note, I understand that with 24-bit addressing, you can address
>up to 16MB of RAM (2^24 is about 16MB), but why is it only 128MB for 32-bits?
>2^32 comes to about 2GB.  Am I to understand that as 32MB SIMMS come out, and
>then 64MB SIMMS, etc., that the ultimate limit is actually 2GB?  Or is there
>some other limitation that is keeping it at 128MB?



a) yeah, what're the other bits wasted on?

b) 2^24 ie *exactly* 16 M, and each address (in this case) is of a byte (right?).

c) 2^32 is *exactly* 4 G.

<a "k" in computerese is not 1000 (as in Kilo), but 1024 (as in 2^10)>


Rich