Difficult to say since I'm not running anything else except a mail server. I use gnome as the desktop and it runs very nicely. I've never tried accessing the mail via the loopback but other than a 3 or 4 second pause when a pop3 connection is attempted remotely, the mail, even with large attachments rockets through. More background though may be helpful. The processor is 1.8G with 384M of ram. Local network is 100baseT ethernet running through a linksys router (acting as firewall and gateway), then cable modem access. I'm using the dns of the cable company but my domain's dns is handled by Zoneedit's dynamic dns service. Openssl is also running. I hope this rings a bell for someone.