By default, archlinux have all repository around the world, you don't need do anything to repositories URL. But some times, if you just want to use one repo directly you can setup archlinux repository manually.Just Edit /etc/pacman.conf, to point to your another URL repository. For this example i'm using this URL -> http://kambing.ui.ac.id/archlinux/
Set up Archlinux Repository Manually For 32 Bit Repositoryopen terminal, or if you still in terminal:
#nano /etc/pacman.confSet like this:
Set up Archlinux Repository Manually For 64bit repository
open terminal, or if you still in terminal
#nano /etc/pacman.confSet like this: (multilib enabled)
Save (Ctrl+x),then run
#pacman -Syto update database. Of repositories.
If done you can continue to upgrade archlinux system by doing "pacman -Syu" or installing application by doing "pacman -S applicationname".
Difference between 32bit and 64bit is just processor, and about ram, 64bit doesn't always shows more than 32bit. For my devices, Intel Atom N455 1gbram with 64 bit system run fine, and the system resources still same when using 32bit on same devices.
And about 32bit application on 64bit, if you enable "multilib" then you can run 32bit application on 64bit.
Enjoy rolling release. :D