The ARM architecture is a good choice for “deeply embedded” apps, like phones, PDA’s and the like, but when you want to run a lot more s/w with demand-paged VM, etc.... we start realizing that ARM isn’t the best way to go. It isn’t so much that the ARM is brain damaged as the reality of when we want to field a phone with all sorts of whizzy features AND we want the battery to last two days in your pocket... choices simply have to be made. MMU’s, FPU’s etc - they have to be left behind.
The ARM’s big advantage is that it really has the lowest power consumption out there (and the current ARM vs. last year’s Atom still gave the ARM the advantage on power consumption, especially when we take the additional chips used with an Atom into consideration), but when we start talking of Windows/OS X as a operating environment, we start expecting more out of the CPU than in the phone/PDA space. The next gen of Atom will take care of this issue tho, and that’s why I’d go with an Atom solution to a tablet over an ARM.
NEWS - Marvell claims first quad-core ARM processor
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Marvell's quad-core implementation can operate at above 1-GHz clock frequency on all four cores providing high performance in those applications that can keep four cores fed with data.
True the ARM is less power, but the Atom is now 1W. The Atom also has the full SSE and floating point capabilities and the ARM doesn’t.