Don’t let yourself be fooled by pure clock speed. In most of the benchmarks, the Celeron lags considerably behind the Pentium 4. The reason is the smaller L2 cache on the Celeron, which has to get by with only 128 kB. The Pentium 4 based on the Willamette core, on the other hand, has 256 kB. But it’s being phased out in favor of the more modern Northwood core - by refining manufacturing down to 0.13 micrometer structures, Intel has managed to squeeze 512 kB L2 cache onto the chip, which is four times the Celeron’s cache. We used the latest Pentium 4 core for the tests in this article.