Intel Pentium 4 processor family

Intel Pentium 4 microprocessors were based on completely new NetBurst micro-architecture, that differed significantly from P6 micro-architecture used in Pentium II/Pentium III microprocessor families. One of key features of Pentium 4 processor was Hyper-Pipelined Technology - 20-stage pipeline, that was two times longer than in previous generation of Pentium processors. While longer pipelines are less efficient than shorter ones, they allow the CPU to reach higher frequencies, and thus increase CPU performance. To improve efficiency of very deep pipeline the Pentium 4 processors included many other features: Trace Execution Cache, Advanced Transfer Cache, Enhanced Branch prediction, Quad Data Rate bus and Hyper-Threading technology. When first released the Pentium 4 architecture included 144 new SIMD instructions called SSE2. Later versions of Pentium 4 processors also included SSE3 instruction set and full set of 64-bit instructions (EM64T).

Intel Pentium 4 microprocessor family consists of the following sub-families:

* Xeon and Xeon MP - high performance versions.
* Pentium 4 - desktop CPU.
* Mobile Pentium 4 and Mobile Pentium 4-M - mobile versions of the CPU.
* Celeron - low-cost version.
* Mobile Celeron - mobile version of the low-cost Pentium 4 processor.

All Pentium 4-branded processors have only one CPU core. Dual-core microprocessors based on NetBurst microarchitecture were branded as Pentium D.