With its Pentium III processors struggling, Intel turned its eyes on a new micro-architecture known as NetBurst, which featured a very deep instruction pipeline and was supposedly capable of scaling to very high clock speeds. This touted scalability was expected to help Intel overcome the threat of AMD, though when the first processors based on this micro-architecture, the Pentium 4 (Willamette) were initially launched, they were still lagging behind their Athlon competitors. In fact, they were arguably not much of an improvement over the Pentium III. However, SSE2 was added for the Pentium 4, following up on the original SSE that was present on the Pentium III and these additional instructions made some difference with the proper application support.
Overall, the early Pentium 4 processors that we saw in 2000 were not at all worth its premium price, high temperatures and power consumption. However, even the early Willamette cores had clock speeds of at least 1.5GHz which meant that they had a numerical albeit false advantage compared to the 1.4GHz maximum managed by the Athlon Thunderbird (which was actually the better performer). This was to result in AMD's attempts to counter any wrong perceptions created by absolute processor clock speeds with concerted marketing efforts in the next couple of years.