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I'm missing something here. I know some of you computer people are going to bitchslap me, but I thought 1 gigahertz was kind of slow by today's standards? The computer I use has a 333 Celeron (megahertz) My wife bought a new one- Pentium 4 and it runs at some ridiculous speed that I don't even like to contemplate- well over 1 gigahertz (1.8 I think). Obviously, I'm missing something.

Come on, inform me! I have assumed the position and await enlightenment!

The Itanium is a 64 bit chip, while PC's have 32 bit chips. A 64 bit chip has a much larger instruction set and address space than a 32 bit chip so, gigahertz aside, it can process more complicated instructions more quickly. A 64 bit chip is more of a minicomputer than a PC, with the capacity to support multiple processes more easily than a 32 bit PC.

This is of particular interest to me because my favorite operating system, OPEN/VMS is being ported to Itanium by HP. VMS is a whole lot more robust than Win 2000 and much easier to use than command line UNIX. Until now, it has been stuck on the dwindling Alpha/VAX minicomputer architecture but this will hopefully give it a new lease on life. If someone could mate OPEN/VMS with a GUI and standard WINTEL applications like Office it would be a really wonderful thing.

We have heard over the last few years, first from Apple, then from AMD about the "Megahertz Myth". Basically what this means is that the clock speed - or Mhz" is not an accurate measure of processing power or speed.

The current slate of P3 and P4 processors have truly amazing clock speeds, but their "pipeline" or path the data takes through the processor is restricted because it is so long. Therefore, less data is processed per clock cycle.

AMD processors, and even more so - Motorola G4 processors have shorter pipelines and therefore don't have the same restriction on amount of data/instructions processed per clock cycle. Because of this, more work is done each clock cycle. It's basically an efficiency issue.

Say that processor "A" can execute 8 instructions per clock cycle.

Processor "B" can execute 5 instructions per clock cycle.

Processor "B’s” clock speed is 50% slower than "B". In the same given time frame, theoretically they would actually process the same total quantity of information., yet processor "A" did it more efficiently. Combine this with the fact that "B" is actually going to do a bit less total output because of inefficiencies in the design.

The Itanium line is shows that Intel is finally admitting this fact. While Mhz (or Ghz) sounds great and still sells consumers, professionals what performance, which does not always come directly from clock speed.

Another monkey wrench is that the software really needs to be optimized for the specific processor architecture.

Aside from better instruction sets & etc., the pathways of the new chip are twice as wide: 64 instead of 32 bits.

Think of it in reverse: When Intel was still producing the 32-bit PII, AMD was making the 16-bit K6. But the performance of the two chips was simular because Intels "300 MHZ PII" was running at 300 MHZ but AMDs "300 MHZ K6" was actually running much faster: more like 550 MHZ. The net effect was that it ran like a "300 MHZ" PII.

As for day-to-day applications most of the reasons you notice your wife's new computer running so fast is not the chip itself but the peripherals like the hard drive. You probably have a 3400 RPM drive and you wife's system probably has a 7200 RPM drive with UDMA 100. She probably has DDR memory too, as opposed to your memory which is probably running at 66 MHZ. Not to mention a superior video card.

Where the processor really comes into play is in rendering graphics or sorting large database tables...When opening Word or something like that, it's everything else in the computer that comes into play.