The main thing about Dell choosing AMD is their market demographics. The average brand name CPU buyer (which is who all the major PC builders sell to) does not know the differences between Intel or AMD, and go to Intel simply because of brand recognition. When people do buy AMD, it is ususally because of the lower price, not really knowing much about the performance of the system compared to an Intel system. Dell may have a contract with Intel where Intel gives price breaks for certain volumes, and therefore it may be beneficial to Dell's bottom line to stick with Intel only. I don't know, but when Dell sells millions of computers, therefore buying millions of processors from Intel only, it is definately a possibility that Intel would do such a thing.
Obviously Dell is doing pretty good with Intel only computers. I mean, their market share has been growing and they captured the #1 spot from Compaq recently. But, it is very doubtful that the reason for that is Intel CPUs only, and they very well may have done it if they used AMD chips as well. I personally don't care either way. Obviously Dell and AMD are both doing pretty damn well in the current situation (both are constantly gaining market share against their competitors). But, you are all right, it may be better for both (but worse for Intel) if Dell and AMD do forge some sort of business alliance.
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