Help a noob buy a kick ass computer for PS.

[foxjedi]

All,
I'm in the market for a shiny new computer, but I don't know much about the hardware, or software of computers. Here's what I want, and perhaps you, kind reader, can direct me towards the right one.
1.) A computer that can run PS with no problems.
2.) Something that can handle games that're coming out in the next year (Warhammer 40k: Dawn of War) with no problem.
3.) Standard stuff like a CD burner.

Now, home much RAM, what video card, etc, should I get? I looked at the alienware page and I had no clue what they wanted me to choose.

Thanks