Yes,
I would not go with the Gateway. I don't know if they have gotten any better in the past couple years, but I Know my brother bought a couple and they were junk. They look real pretty on the outside but they put junk hardware on the inside. Any computer company that puts the big footprint quantum fireball hard drive in their computer is off my list for good! .
If you aren't familiar with assembly of the computer/OS installation you can peice a computer together from www.accessmicro.com or you could order a custom made Dell PC (they appear to be pretty straight forward and don't use cheap-o parts that I have seen). If you want any more info let me know. Myself or anyone of us here should be able to assist.
you might not need the mpc right away, many of the things that it does can be handled by your software. i would save your money here and work on getting as nice of signals into your computer as possible.
i think the audiophile soundcard should be good enough for now.
what about some real drum machines? if you want street cred you should start looking for some cool outboard gear. for now you might want to pick up some sample CDs of loops and drums and build your beats in acid. later you can dump these into the akai, and work with them in that box (preferable if you are playing out).
what kind of hiphop? this is pretty important. if you want to sound like the antipop consortium you are going to want totally different gear than if you want to sound like nelly.
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