3gb in my lappy and 512mb in my server. both are running linux mint 7 gnome 32bit. the server is only a 1.2ghz amd duron and is used as a samba/sftp file server and my laptop is an amd athlon x2 QL-60 1.9/core. i only use about 200mb on my laptop usually and the server typically uses about 250mb (it has to run VNC and serve a massive amount of data AND run gnome). i never seem to use more than about 1.5gb of ram on my laptop even with firefox, virtualbox, synaptic, and rhythymbox running. 1gb of ram would be fine for you if you werent using that stupid MACROsoft system. anyone who uses windows get's what they deserve when they get infested with viruses.
My desktop has 3gb laptop 1gb I also have a computer that I leave on all the time with xbuntu installed at it has 512mb ram I use it for filesharing laptop is runining ubuntu nexbook remix desktop is running windows vista home premium!