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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PPC 970 versus x86
by KoenigMKII on Thu 10th Jul 2003 23:42 UTC

I found that article by Nicholas Blachford a very informative read.

IBM's web site confirms your power dissapation figures for the various 970 chip frequencies. Impressive work from Big Blue.

My only problem with the article is not the answers it provides in comparing PPC 970 v x86 (IA-32) but why make such an odd comparison in the first place?

Intel knows that IA-32 is nearing the end of its useful life, that is why they spent so much time and money together with HP to create the VLIW IA-64 arcitecture.

The correct comparison is Itanium 2 (and especially the upcoming "Deerfield" version) versus PPC 970. The reason is that these two have more similar 64-bit addressing, memory bandwidth, SMP scalability and floating point math capabilities, and both are manufactured in 130 nanometer copper processes.

Deerfield will have a much more similar cache size to PPC 970, but we will have to wait until the Intel chip comes out before the complete system testing could be done.

Why don't Apple compare the Dual G5 (970) Mac against the allready shipping HP ZX-6000 Dual Itanium 2 Workstation??

I also think your implication about the IA-32 software base not making an eventual migration to IA-64 does not take into account the "IA-32 execution layer" (code name: btrans) feature coming out for linux-64 and Windows XP 64-bit.

Intel claims that IA-32 software run on an IA-64 system via the "IA-32 execution layer" will provide a GHz equivalent, ie. 1.5 GHz Itanium 2 will run IA-32 software at the same speed as a 1.5 GHz Pentium 4. Thats good enough IMHO.

When memory technology improves to the point when an 8GB memory module is the minimium size commonly produced, then that is the time for the 64-bit chips to take over in new desktop computer systems sold.

I think that by the time that happens then the current IA-64 chip together with the "IA-32 execution layer" will be very, very fast indeed. Then IA-32 software will migate with little or no resistance.

If necessary the Intel cash reserve will be partly used to use differential pricing to boost IA-64 and kill off IA-32 in the same way it killed off the 486 with aggressive Pentium pricing. Since its a battle Intel cannot afford to loose, they WILL go all out.

Then IMHO we have a "Final Unity" in which Intel can drop IA-32, and go all out on IA-64 production in an attempt to crush the PPC with sheer economy of scale.

At the end of the day, software availability is the key factor. PPC is a great technology, but without plentiful native software its just another Betamax.