These Celerons were for socket 478 and were based on the Willamette Pentium 4 core, being a completely different design compared to the
previous Tualatin Celeron. These are often known as the Celeron 4. Their L2 cache (128 KB) is half that of the Willamette-based Pentium 4's 256 KB of L2 cache, but otherwise the
two are very similar. With the transition to the Pentium 4 core the Celeron now featured SSE2 instructions. Willamette Celerons were launched 15 May 2002. In Intel's
"Family/Model/Stepping" scheme, Willamette Celerons and Pentium 4s are family 15, model 1, and their Intel product code is 80531.
These socket 478 Celerons are based on the Northwood Pentium 4 core, and also have 128 KB of L2 cache. The only difference between the
Northwood-128-based and the Willamette-128-based Celeron is the fact that it was built on the new 130 nm process which shrank the die size, increased the transistor count, and
lowered the core voltage from 1.7 V on the Willamette-128 to 1.52 V for the Northwood-128.
Kindly donated by Pauli Rautakorpi.
Prescott-256 Celeron D processors, initially launched 25 June 2004, featuring double the L1 cache (16 KB) and L2 cache (256 KB) as compared to the previous
Willamette and Northwood desktop Celerons, by virtue of being based on the Prescott Pentium 4 core. It also features a
533 MT/s bus and SSE3, and a 3xx model number (compared to 5xx for Pentium 4s and 7xx for Pentium
Ms). The Prescott-256 Celeron D was manufactured for Socket 478 and LGA 775, with 3x0 and 3x5 designations from 310 through to 355 at
clock speeds of 2.13 GHz to 3.33 GHz.
The Celeron D was a major performance improvement over previous NetBurst-based Celerons. This CPU also had the addition of SSE3 instructions and the higher FSB which only contributed to
this already impressive gain.
Based on the Cedar Mill Pentium 4 core, this version of the Celeron D was launched 28 May 2006, and continued the 3xx naming scheme. The
Cedar Mill Celeron D is largely the same as the Prescott-256, except with double the L2 cache (512 KB) and based on a 65 nm process. The Cedar Mill-512 Celeron D is LGA
775 exclusive. The main benefits of the Cedar Mill Celerons over the Prescott Celerons are the slightly increased performance due to the larger L2 cache, higher clock rates, and
less heat dissipation, with several models having a TDP lowered to 65 W from Prescott's lowest offering of 73 W.