Hexus has posted a review on the Pentium 4 processor. They talks about architecture changes and other features of the P4.

Intel needed to kill this CPU quickly (AMD´s new 7th Gen processors), so they started new and clean. They had the Pentium Pro, P2, P3, Xeon and Celeron 2 which were all the old "style" running in the P6 architecture. To try and combat the market Intel added things like SSE and MMX which were in competition to AMD´s 3DNow technology. They also changed the format of the interface from Slot 1 to Socket 370. The other changes they have done are on DIE cache and other small changes, but they carried on working on the same original template

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