i work for HP

I think you're talking about the elite series pavilion right? that thing is pretty 1337, it has like 3gigs of ddr2 which aint bad

But yeah obviously building it yourself is going to be cheaper... But if you're not one to tinker around with it yourself i'd go with a premade one... hp has 24/7 customer support and lotsa other goodies aside from the computer.

I've built all of the computers I've owned, and sometimes its a pain when later on you realize that it wasn't such a great choice to use xxx motherboard with xxx sound or video card bc every once in a while xxxx will happen, and bs like that.

Just go to a private computer dealer like Monarch computers, or Ginstar Computers... They'll build you an insane computer to your spec, and can throw a warranty on there.
RAM is dirt cheap right now make sure you get at LEAST 4gb