Well, It depends on what you plan on using it for. If you want to play a lot of games, go for the Alienware and just upgrade the RAM to 1 gig and HDD to 60GB.
If you dont plan on using it for big gaming, maybe just something that runs faster soyou can play music or work with PS(just examples) than go for the Dell.

Get what really fits what you need and the cost, not worth $3000 if your not gonna be playing games like WoW and D2 and a bunch of others. The Dell is pretty good money wise. I would prolly just upgrade RAM, maybe Processor and the HDD. That way it will be better in the long run, instead of buying a new one in a year or so.

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