By Jim Forbes

Talk about making a leap. Pentium processor speeds have tripled in the past three years. But if all goes well at Intel in just the next 12 to 18 months, the next hot processor speeds will be 250MHz and then 300MHz, a total jump of 100MHz-almost double the current 166MHz version.

That's a realistic goal, provided Intel deals with a couple of key issues. The most important of those is heat. The faster the processor, the more heat it produces. Running flat-out, Intel's current 200MHz Pentium Pro can put out as much heat as 17 watts, about the same amount of heat generated by a lightbulb.

New packaging for Pentium processors, dubbed PPGA (for plastic pin grid array), incorporates a copper slug that dissipates heat created by the chip. With it, Intel may be able to goose performance without causing overheating problems. Also important are the new manufacturing processes that allow the company to build parts using smaller geometries. Smaller feature size on a processor translates to faster operation. As a result, Intel may be able to deliver a 300MHz Pentium before the nearly four-year-old line of Pentium processors becomes yesterday's news.

At the same time, Intel is expected to aggressively expand its line of Pentium Pro processors. In fact, this chip could have clock rates twice that of the P5 line. Assuming Intel can reduce the line widths on this chip from 0.35 micron to 0.25 micron or less, you could see Pentium Pros with clock speeds of 400MHz to 600MHz, according to industry sources briefed by Intel on its plans for the next 12 to 18 months.

The biggest change you're likely to see this year is the introduction of the P55C Pentium family, which incorporates microcode and other new technologies that make it possible to run multimedia applications faster and more efficiently.

MMX (multimedia extensions) technology uses a technique called single instruction multiple data (SIMD) that allows the chip to process multiple pieces of data in parallel. For example, a single instruction could operate on multiple pixels in a graphic at the same time. Thanks to SIMD and the more than 50 new instructions that have been added to the P55C's design, this new member of the Pentium family can more efficiently run 2-D, 3-D, communications, audio and video applications.

MMX should make its first appearance in a 200MHz version of the P55C late this year. According to company documents, Intel is expected to use MMX technology in most of the new P5 and P6 processors it introduces in calendar 1997.