Yes a G4 was quite a bit faster than a P4 clock for clock, especially on floating point and vector operations and used quite little power too. You can go watch

Yes a G4 was quite a bit faster than a P4 clock for clock, especially on floating point and vector operations and used quite little power too. You can go watch the annual videos where they show photoshop benchmarks running faster on the G3, G4 and G5s. But Intel did take the lead on occasion and kept up mostly. XP also felt faster in UI than early Mac OS X versions, although it did more and improved later on.