Pentium M

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Image:Pentium m 2006.gifIntroduced in March 2003, the Pentium M is an x86 architecture microprocessor designed and manufactured by Intel and forms part of the Intel Centrino platform. The processor was originally designed for use in laptop personal computers, thus the "M" for mobile. It was codenamed "Banias" before its introduction. The codenames of the Pentium M are all locations in Israel, the location of the Pentium M design team. Image:Pentium M.jpg See also Intel P6

1 Banias
2 Dothan
3 Core Solo & Core Duo
4 See also
5 External links

The Pentium M represents a new and radical departure for Intel, as it is not a low-power version of the desktop-oriented Pentium 4, but instead a heavily modified version of the Pentium III Tualatin design (itself based on the Pentium Pro core design). It is optimised for power efficiency, a vital characteristic for extending notebook computer battery life. Running with very low average power consumption and much lower heat output than desktop processors, the Pentium M runs at a lower clock speed than the contemporary Pentium 4 desktop processor series, but with similar performance (e.g. a 1.6 GHz Pentium M can typically attain the performance of a 2.4 GHz Northwood Pentium 4 (400 MHz FSB, 100 MHz quad-pumped) with no Hyper-Threading Technology). Image:Pentium M Dothan.jpg The Pentium M couples the execution core of the Pentium III with a Pentium 4 compatible bus interface, an improved instruction decoding/issuing front end, improved branch prediction, SSE2 support, and a much larger cache. The usually power-hungry secondary cache uses an innovative access method to avoid switching on any parts of it which are not being accessed. Other power saving methods include dynamically variable clock frequency and core voltage, allowing the Pentium M to throttle clock speed when the system is idle in order to conserve energy. The latest innovation in this department is also the incorporation of the SpeedStep 3 technology which has enhanced sleep stages in comparison to the previous versions of SpeedStep. With this technology, a 1.6 GHz Pentium M can effectively throttle to clock speeds of 600 MHz, 800 MHz, 1000 MHz, 1200 MHz, 1400 MHz and 1600 MHz. The existence of these intermediate clock states allows the CPU to better throttle clock speed as per requirement. Another remarkable feature of the Pentium M is its extremely low power dissipation which varies from 5 watts when idle to 27 watts on full load. This feature is extremely useful to notebook manufacturers as it allows them to bundle the Pentium M into thinner, lighter and smaller notebooks.

Although Intel has marketed the Pentium M exclusively as a mobile product, motherboard manufacturers such as AOpen, DFI and MSI have been shipping Pentium M compatible boards designed for enthusiast, HTPC, workstation and server applications. An adapter, the CT-479, has also been developed by ASUS to allow the use of Pentium M processors in selected ASUS motherboards designed for Socket 478 Pentium 4 processors.

Pentium M processors are gaining a lot of attention from the embedded systems industry. The low power consumption of the Pentium M allows the design of fanless and highly miniaturized embedded PCs, such as the Toradex Midget.

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Banias

The first Pentium M was identified by the codename Banias with no model number, or model number 705. It was manufactured on a 130 nm process, was released at frequencies from 1.3 GHz to 1.7 GHz using a 400 MHz FSB (100 MHz quad-pumped), and had 1 MiB of Level 2 cache. The core average TDP (Thermal Design Power) is 24 watts.

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Dothan

Image:Pentium M Dothan Backside.jpg Intel launched its improved Pentium M, formerly known as Dothan, on May 10, 2004. Dothan Pentium M processors are among the first Intel processors to be identified using a "processor number" rather than a clockspeed rating, and the mainstream versions are known as Pentium M 715 (1.5 GHz), 725 (1.6 GHz), 735 (1.7 GHz), 745 (1.8 GHz), 755 (2.0 GHz), and 765 (2.1 GHz).

These 700 series Pentium M processors retain the same basic design as the original Pentium M, but are manufactured on a 90 nm process, with twice the secondary cache. Die size, at 84 mm², remains in the same neighborhood as the original Pentium M, even though the 700 series contains ~140 million transistors, most of which make up the massive 2 MiB cache. TDP is also down to 21 watts (from 24.5 watts in Banias), though power use at lower clockspeeds has increased slightly. However, tests conducted by third party hardware review sites show that Banias and Dothan equipped notebooks have roughly equivalent battery life.

The processor line has models running at clock speeds from 1.0 GHz to 2.26 GHz as of July 2005. The models with lower frequencies were either low voltage or ultra-low voltage CPUs designed for even better battery life and reduced heat output. The 718 (1.3 GHz), 738 (1.4 GHz), and 758 (1.5 GHz) models are low-voltage (1.116 V) with a TDP of 10 W, while the 723 (1.0 GHz), 733 (1.1 GHz), and 753 (1.2 GHz) models are ultra-low voltage (0.940 V) with a TDP of 5 W.

Revisions of the Dothan core were released in the first quarter of 2005 with the Sonoma chipsets and supported a 533 MHz FSB (133 MHz quad-pumped) and XD (Intel's name for the NX bit). These processors include the 730 (1.6 GHz), 740 (1.73 GHz), 750 (1.86 GHz), 760 (2.0 GHz), and 770 (2.13 GHz). These models all have a TDP of 27 W and a 2 MiB L2 cache.

In July 2005, Intel released the 780 (2.26 GHz) and the low-voltage 778 (1.60 GHz).

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Core Solo & Core Duo

Template:Main The next generation of processors using the Pentium M microarchitecture, codenamed Yonah, has been released under the Intel Core brand, as Core Solo and Core Duo.

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External links

**List of Intel microprocessors | List of Intel CPU slots, sockets**
Intel processors 4004 \| 4040 \| 8008 \| 8080 \| 8085 \| 8086 \| 8088 \| iAPX 432 \| 80186 \| 80188 \| 80286 \| 80386 \| 80486 \| i860 \| i960 \| Pentium \| Pentium Pro \| Pentium II \| Celeron \| Pentium III \| XScale \| Pentium 4 \| Pentium M \| Pentium D \| Pentium Extreme Edition \| Xeon \| Core \| Itanium \| Itanium 2 (italics indicate non-x86 processors)