MMX: Fact vs. fiction

Despite monumental hype throughout the industry, Intel's (INTC) MMX today is part multimedia technology and part smoke screen.

As Intel revs up its MMX marketing machine and puts the final building blocks of the MMX computing structure into place, including new chipsets and new circuit boards for notebooks, PC users may be well advised to understand that MMX, in the purest sense, is a technology that has not really arrived.

The issue boils down to the definition of MMX: It is a set of new instructions that can speed up applications written to take advantage of the new technology. The problem is that there are few applications today that do this.

"This is on the order of dozens [of applications]. There are a few very-high-profile applications and some niche applications. So is this a pervasive technology? No," said Dean McCarron, an analyst at Mercury Research in Scottsdale, Arizona.

In fact, what most users are getting today is not MMX at all but a new Pentium chip with some internal design improvements and nothing more. In short, instead of MMX, users are getting a new P55C--the code name for the newest Pentium chip design--vs. the older P54C "classic" Pentium design.

"You're not really getting MMX. You've been told you're getting MMX, but what you're really getting is an improved [chip] design that happens to be called MMX," McCarron said.

For people using applications that don't take advantage of the multimedia technology--in other words, most of the applications out there today--the MMX moniker is, practically speaking, meaningless. Granted, this could change as more applications come out, but for the foreseeable future MMX really has little to do with dramatic speed improvements based on specific software applications that use the new instructions.

How does this translate into raw performance numbers? Instead of the dramatic 300 or 400 percent boost in performance seen on some of these relatively scarce MMX-aware applications, what most users will see is a modest improvement between 10 and 20 percent--and probably closer to 10 percent, McCarron said. And even this modest speed increase is based solely on design improvements of the P55C Pentium, such as a larger cache and fixes to the way data flows inside the processor.

Moreover, as Intel begins work on the next-generation MMX 2, it is becoming apparent that the current version of the technology needs some tuning up. "If you were to design MMX from the ground up, you wouldn't do it the way it's implemented today. MMX was essentially bolted on to the chip," McCarron noted.

Intel is an investor in CNET: The Computer Network.