first of all me a newbie to novell

i hav current nw6 server with gw6.5 on it
P4 .2.4ghz with 500mb SDRAM

i wish to change the sytem to a more powerful one.
is it support DDR?
and wat is the maximum HDD capacity it will support?
wats the best solution to take backup of the GW?

thnx in advnc
pok