XPS come in towers and laptops. But I don't think Oasis has a laptop unless he's using a docking station. Otherwise there would be no point in buying a new monitor.
I built a computer from scratch at the beginning of October. Picked up an AMD 955 X4 processor, 4gbs of RAM (Corsair), 500gb HD, and an XFX Radeon 6850. The PSU I bought was also pretty much base-line; it was an Antec that had just a little bit more output than my card requires. For only $600, I'm playing pretty much every game under the sun on high.
I had an i7 build but it was something like $200 more, and I wanted to spend as little as possible while maintaining enough quality to justify the purchase. Pretty crappy cheap case too. It's an Antec, but one of their cheapest ones available. Already broke one of the USB ports on front.
Feels good, man.
Now I just need to buy a big monitor that'll let me run at 1080 and I'll be happy. (gonna be expensive. >_>)
Don't worry about how. Just know that somehow, global warming is the culprit.