A major question for some people getting ready to buy a high-end system is whether they want or need to have two processors available to them. For anyone doing video editing,
multi-threaded applications, or a lot of multitasking the answer is a very clear 'yes'. Then the question becomes whether two separate processors (as in a dual Xeon or Opteron ystem) is the way to go, or whether a single dual core processor (like a Pentium D or Athlon64 X2) will do just as well. Dual CPU vs dual core -- which is better?!
Intel did not increase the speed of their front-side-bus (the connection between the CPU and the motherboard) when they switched to dual-core, meaning that though the
power doubled, the amount of bandwidth for each core did not. This puts a bit of a
strain on the Intel design, and likely prevents it from being as powerful as it could
be. To counteract this effect, Intel continues to use faster system memory to keep information supplied to the processor cores.
AMD, on the other hand, does not use a front-side-bus in the traditional sense. They use
a technology called HyperTransport to communicate with the chipset and system memory,
and they have also moved the memory controller from the chipset to the CPU. By having
the memory controller directly on the processor, AMD has given their platform a large
advantage, especially with the move to dual-core. The latest generation of AMD single-core processors can use single- or dual-channel PC3200 memory, but it is interesting to note that even though dual-channel operation doubles the memory speed, it oes not double the actual memory performance for single-core processors.