Pentium 4

The Pentium 4 brand refers to

Pentium 4

Intel's line of single-core mainstream and high-end desktop and laptop central processing units (CPUs) introduced on November 20, 2000^[1] (August 8, 2008 was the date of last shipments of Pentium 4s^[2]). They had the 7th-generation microarchitecture, called NetBurst, which was the company's first all-new design since 1995, when the Intel P6Pentium Pro CPUs had been introduced. NetBurst differed from the preceding Intel P6 (Pentium III, II, etc.) by featuring a very deep instruction pipeline to achieve very high clock speeds^[3] (up to 3.8 GHz) limited only by TDPs reaching up to 115 WPrescott and Prescotts 2M cores^[4] (a high TDP requires additional cooling that can be noisy or expensive). In 2004, the initial 32-bit x86 instruction set of the Pentium 4 microprocessors was extended by the 64-bit x86-64 set. microarchitecture of the in 3.4 GHz –3.8 GHz

The first Pentium 4 cores, codenamed Willamette, were clocked from 1.3 GHz to 2 GHz and the first Willamette processor was released on November 20, 2000 using Socket 423. Notable with the introduction of the Pentium 4 was the 400 MHz FSB. It actually operated at 100 MHz but the FSB was quad-pumped, meaning that the maximum transfer rate was four times that of a normal bus, so it was considered to run at 400 MHz. The AMD Athlon's double-pumped FSB was running at 200 MHz or 266 MHz at that time.

Pentium 4 CPUs introduced the SSE2 and, in the Prescott-based Pentium 4s, SSE3instruction sets to accelerate calculations, transactions, media processing, 3D graphics, and games. Later versions featured Hyper-Threading Technology (HTT), a feature to make one physical CPU work as two logical and virtual CPUs. Intel also marketed a version of their low-end Celeron processors based on the NetBurst microarchitecture (often referred to as Celeron 4), and a high-end derivative, Xeon, intended for multiprocessor servers and workstations. In 2005, the Pentium 4 was complemented by the Pentium D and Pentium Extreme Edition dual-core CPUs.