As we remember, during the official launch of Pentium 4 processors with 2.4GHz core clock, Intel said that very soon they would start making these CPUs from new 300mm wafers instead of the older 200mm ones. They also reported that to move to a more progressive technology, they had to introduce some changes to the core design, which resulted into smaller die size, reduced from 145sq.mm to 131sq.mm. Nevertheless, we haven’t heard about the shipments of Pentium 4 processors based on smaller die since then.

However, a few days ago Intel has finally spread the official announcement about the company having started to ship the new processors based on smaller die. The new CPUs boast smaller production costs and at the same time are designed to support higher core frequencies, which should of course increase their overclocking potential.

The die update touches upon all Pentium 4 models with the frequencies from 1.8GHz to 2.53GHz. The improved CPUs will not have a different core stepping from the predecessors. It will be the same B0. The CPUID will also remain the same. However, you will still be able to distinguish between the old and the new CPUs by the location of passive components at the bottom of the CPU and by the new S-Spec. So, the processors born from 300mm wafers will feature the following S-Spec:

• Pentium 4 1.8A – SL66Q
• Pentium 4 2A – SL66R
• Pentium 4 2.20 – SL66S
• Pentium 4 2.26 – SL6D6
• Pentium 4 2.40 – SL66T
• Pentium 4 2.40B – SL6D7
• Pentium 4 2.53 – SL6D8

Note that Pentium 4 with C0 die stepping, which are to come a bit later (we have already mentioned them in our news), will also be based on 131mm enhanced core.