We are buying the Dell Optiplex 755 with Intel dual core processors here at work and they seem to be pretty good. Get min 2 gig ram and XP pro. We do the 3 year warranty and it seems to be cost effective for us. If you really worry about data, you can have it built with two drives and RAID. Watch your CPU speed. Anytime you really crank up the speed, you run into heat problems. Those are microwaves running around in that thing for crying out loud. Anything over 2.4 g seems to be courting trouble.