Hardly. $1500 I'd say. Most of that budget would be the videocard(s).
Vista only needs 1GB to run. BF2142 needs 2GB, thats easy enough, almost standard in gaming now.
Nothing makes a gaming PC like the videocard(s). You build a gaming PC around the videocard(s).
$1500 if thats all you need to do. You won't be getting a crazy soundcard, etc.
I just did one in a hurry with a Core 2 Duo processor. Came to $1500. It had Dual 7900GTs. But it was missing an awesome soundcard, a second Raptor Hard Drive, etc. All the "luxury" stuff was out, but it gives you an idea of what you need to get.