<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body text="#000000" bgcolor="#ffffff"> On 07/04/2011 15:28, Dave Hanson wrote: <blockquote cite="mid:BLU0-SMTP20354E2E40E71C8E3E16C65CDA40@phx.gbl" type="cite"> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> On 07/04/11 14:04, <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:ubuntu-uk-request@lists.ubuntu.com">ubuntu-uk-request@lists.ubuntu.com</a> wrote: <blockquote cite="mid:mailman.14314.1302181463.9230.ubuntu-uk@lists.ubuntu.com" type="cite"> <pre wrap="">On 7 April 2011 13:54, Lee Williams <a moz-do-not-send="true" class="moz-txt-link-rfc2396E" href="mailto:lee.willy1977.williams@gmail.com"><lee.willy1977.williams@gmail.com></a> wrote: </pre> <blockquote type="cite" style="color: rgb(0, 0, 0);"> <pre wrap="">> It's not a problem installing 32bit on a machine with > ~3.5GB ram... rather > the memory after the ~3.5GB or so is not "dedicated to system resources"; > rather, system resources have used up the remaining memory *addresses*, so > the memory cannot be seen nor used by anything, as it has no address. When > 2GB RAM is installed, system components taking up 1GB or so of addresses has > no effect, as there are 4GB of addresses in total, meaning 3GB of addresses > are left available for the 2GB of RAM. > </pre> </blockquote> <pre wrap="">I had to read that a few times, and it still makes no sense. Fact is an install of Ubuntu on 32-bit system _can_ see and _use_ all of the RAM. Al. </pre> </blockquote> I run 8gb of ram on my laptop (64 Bit) and Ubuntu recognises 7.5gb of it, Not too sure what you guys are getting at to be honest. Won't he be fine with the amounts he intends to add? Dave </blockquote> Hi, Sorry if I've caused confusion. I've not tested it with Ubuntu but a kernel running with PAE (Physical Address Extension) supported and enabled on a processor that supports PAE too will allow a user to have up to ~64GB of memory and the system will see and use all of that. The ~4GB limit is an historic limit for 32bit processors due to the memory addresses available to it... however see <a class="moz-txt-link-freetext" href="http://en.wikipedia.org/wiki/Physical_Address_Extension">http://en.wikipedia.org/wiki/Physical_Address_Extension</a> for more information on what PAE does to get around it. PAE is not needed with a 64 bit processor on 64bit implementation on your OS as the memory addresses available bring the "limit" up to if I remember correctly around 256TB... :o Hope that clarifies it, again sorry if I've caused confusion. Regards, Lee. </body> </html>