Dell doesn't <need> Alienware, but here's the thing:
Right now Dell is sitting on a buttload of cash. It's no secret that shareholders have been pressuring Dell to spend their capital in some manner. And shareholders have been generally displeased with Dell's inability to grow. Right now Dell is in a period of no growth. They're making money, but they're not growing. The only part of their business that's even remotely growing right now is their printer business... and even that has stalled. In fact, if you look at the 12 month stock report of Dell, it's been steadily falling.
http://quote.morningstar.com/Quote.html?ticker=DELL&pmts=SQ2&pgid=qtqnnavrel2
Anyways, when you have this much cash you typically do 1 of 2 things: pay out dividends to your shareholders or buy something. Wal-Mart, M$, and ExxonMobile are going through the same troubles.
At this point in Dell's strategic situation I think it makes more sense for Dell to spend their cash on a printer company like Lexmark. Right now Lexmark Optra's and T630's are frigin hot. Dell already has a rebanding deal w/ Lexmark so it wouldn't be that much of a stretch for Dell to buy Lexmark. This, to me, makes more sense from a competitive and growing point of view. But Lexmark can't be had for less than a couple billion at least. Alienware could probably be had for around $500,000 million or less.
Alienware made approximately $170,000,000 in revenue last year. That's nothing! The piddly company I work for made six times that last year. In retrospect Dell made $49 billion in NET revenue last year. Because alienware is a private company, they are not obligated to share their earnings with the public. So who knows if alienware is even profitable?
Indeed this probably is just a way for Dell to increase revenue in a growing market (if it even is one. as madmodmike pointed out this is nothing more than speculation and rumor). The
only reason Dell would buy Alienware is for revenue growth and maybe (this is a stretch) for plausible deniability to their good friends at Intel.
Generally speaking, there's not a whole lot of money to be made in the gaming pre-built computer arena (right now). I've seen a few reports that the high end enthusiast market is growing. Additionally gaming PC's have an extremely high margin.
Just my financial thoughts. ;-)
-mpjesse