Linked by Nicholas Blachford on Wed 9th Jul 2003 16:43 UTC
Talk, Rumors, X Versus Y This article started life when I was asked to write a comparison of x86 and PowerPC CPUs for work. We produce PowerPC based systems and are often asked why we use PowerPC CPUs instead of x86 so a comparison is rather useful. While I have had an interest in CPUs for quite some time but I have never explored this issue in any detail so writing the document proved an interesting exercise. I thought my conclusions would be of interest to OSNews readers so I've done more research and written this new, rather more detailed article. This article is concerned with the technical differences between the families not the market differences.
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Ugh
by stingerman on Thu 10th Jul 2003 17:34 UTC

That is the point, the CISC instructions are fat and require the CPU to break them down further in micro-code. In addition CISC instructions are not uniform in size which means that scheduling, out of order processing, decoding, etc. are a lot more expensive. The RISC vs CISC debate is long dead. RISC won a long time ago and x86 has been adopting as much RISC type design over the years as possible. The problem as the Author and even Intel has pointed out, is that the current generation of processors require compatibility with the original x86 CISC platform. Intel's Itanium design finally walks away from that, but it has been a failure, last year selling only 700 units. It is going to be a herculean effort for Intel to break free from its legacy processors. IBM does not have these kinds of handcuffs on them, the PowerPC Architecture had the foresight to be well designed as a 64-bit RISC instruction set since its inception.

That is why the G5 is such a clean and elegant design.