Memory Problem Ubuntu 8.04

[cameron365]

Hi,

I had a xen server with 2 GB of memory, i have moved it (HDD) to new hardware which have 4Gb of RAM but now the server is up when i use 'xm top' it show's me Mem: 3397676k instead of 4GB.

can someone tell me what is the problem?

[falko]

What's the output of uname -a?

[cameron365]

What's the output of uname -a?

this is the output of uname -a

Linux 2.6.24-16-xen #2 SMP Sun Apr 20 05:49:43 JST 2008 i686 GNU/Linux

[falko]

You have a 32bit system which can use only about 3GB of RAM. If you want to use the full RAM, you need a 64bit OS.
http://answers.yahoo.com/question/index?qid=20090701012237AAlCYFg

[cameron365]

Can i upgrade it to 64bit version nor i have to reinstall the OS?
sorry for any inconvenience:)
by the way when my hardware shows 4Gb of memory that mean i can install 64bit version of ubuntu, isnt it?

[falko]

You have to reinstall the system, you cannot update from 32 to 64 bit.