actually, my [un-tech-educated] step-dad just got a new laptop and ended up going with the x64 because the guy told him to at best buy or one of those types of places... and i was surprised that they would even attempt to sell a home user an amd just because it is 64-bit. Also, it is no where near fair to compare an xp to an x2.... they were/are both great at one point in time. IMO, a 64 bit processor is not necessary for an averagish user. True, some games do use the 64 bit capabilities of the processor, but it will take a while to catch on.
Getting an x2 isnt a bad idea, but think about what your using it for... if it is going to be used for hard core gaming, 3d mapping, or something of the sort, get the x2.... however unless its a prebuilt system, you'd have to return all the parts and basically start over because the core duo is a socket 478, x2 is a socket 939.... which means new mobo, new psu possibly, new memory.... ah you get it
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