The PowerPC chips in the G3 and G4 became a central part of Apple's branding and marketing for the Power Macintosh. For example, the Blue and White G3 features the letters "G3" on the side that are fully one-third the height of the entire case, a significant departure from the small labels typically used on prior Macintosh computers. And when the Power Mac G4 was introduced, print ads included pictures of the G4 chip and mentioned its AltiVec instruction set by its own marketing name, "Velocity Engine". A related element of Apple's marketing strategy, especially after mid-2001, was to highlight what they described as the "Megahertz myth", challenging the belief that a processor's clock speed is directly correlated with performance. This had become important with the introduction of Intel's Pentium 4, which featured significantly higher clock speeds than competing chips from Sun, IBM, and AMD, but without a corresponding performance benefit.