Intel Pentium 4
Higher clock speed (average 2.4-3.4GHz)
4 gates
120 million instructions per second
33 stage pipeline
AMD AthlonXP/64 series
Lower clock speed (average 1.8-2.4GHz)
2 gates
345 (XP) to 375 (64) million instructions per second
16 stage pipeline
But what do all these numbers mean?

Clock speed is the speed at which the processor executes instructions. A Pentium 4 can pump 1Hz per nanosecond through each of its four gates, for a total of 4Hz/ns. The AthlonXP/64 can pump 1Hz per nanosecond through each of its two gates, for a total of 2Hz/ns. However, the Pentium4 only outputs 120 Million Instructions per Second (MIPS) on each Hz, while the AthlonXP can produce 345MIPS, and the Athlon64 can produce 375. What this means is that while the Pentium 4 is running at a higher clock speed, a comparable Athlon can run just as fast. When you purchase and AMD processor it is labeled as “Athlon64 2800+” which means it can about as fast as an Intel Pentium 4 2800MHz (2.8GHz) processor, however the AMD processor is only running 1.8GHz.