Server Upgrade

Thinking about upgrading my ftp server. It presently consist of a amd 64 3000+, 2Gb ddr, 120Gb main drive, 200Gb and 250gb storage drives. I have a Nvidia 6600 w/256Mb on the card. I also have dvr burn and so on. It is currently running Windows XP Professional with Serv-U as my FTP Program. The pc runs pretty good but I think it is time to upgrade to a dual core so it can double as my game server.