Oh yeah, post over in the homebuilt systems section about this question, sure you will get a lot of responses.
But for example, here's what one guy was looking at for 400 bucks. For example, the 4670 video card he's looking at is fairly comparable to the 9600gt I use in my rig. Mind you I'm using my card with a 22 inch monitor. So if he can do that for 400 bucks, get some suggestions around here, we should be able to hook you up with a nice new build, plus a copy of Windows and lcd for that money you are wanting to spend. I am very certain you will be much happier.