Intel Celeron (Willamette) microprocessor family

Intel Celeron Willamette CPU family was the first Celeron family based on NetBurst micro-architecture. The Celeron microprocessors used modified version of Pentium 4 Willamette core. The size of level 2 cache in this core was slashed in half - from 256 KB to 128 KB, in all other aspects the core didn't change. Like Pentium 4 Willamette CPUs, the Celeron microprocessors had 20-stage pipeline, 16 KB data cache, instruction trace cache for approximately 12000 micro-operations, quad-pumped 100 MHz Front Side Bus (effectively 400 MHz FSB), included SSE2 instructions and were manufactured on 0.18 micron technology. Celerons and Pentium 4 Willamette processors had the same core voltage and similar power requirements. The Celerons were packaged in 478-pin Flip-Chip PGA package and worked in socket 478 motherboards.

Performance of Willamette Celeron microprocessors was close to the one of Pentium 4 processors with the same core. On average, the Celerons were 10% slower than Pentium 4 CPUs. It's important to note, though, that by the time Intel released Willamette Celeron processors the Pentium 4 Willamette core was already obsolete and it had been replaced by Pentium 4 Northwood core.