Gecko's CPU Library

Intel Core 2 (Kentsfield) processors

Introduction: November 2006


The Core 2 brand refered to a range of Intel's consumer 64-bit dual-core and 2x2 MCM quad-core CPUs with the x86-64 instruction set, based on the Intel Core microarchitecture, derived from the 32-bit dual-core Yonah laptop processor. Note: the Yonah's silicon chip or die comprised two interconnected cores - each similar to those branded Pentium M. The 2x2 MCM dual-die quad-core CPU had two separate dual-core dies (CPUs) - next to each other - in one quad-core MCM package. The Core 2 relegated the Pentium brand to a lower-end market, and reunified laptop and desktop CPU lines, which previously had been divided into the Pentium 4, D, and M brands.

The Core microarchitecture returned to lower clock speeds and improved processors' usage of both available clock cycles and power compared with preceding NetBurst of the Pentium 4/D-branded CPUs. Core microarchitecture provided more efficient decoding stages, execution units, caches, and buses, reducing the power consumption of Core 2-branded CPUs, while increasing their processing capacity.

The Core 2 brand was introduced on July 27, 2006 comprising the Solo (single-core), Duo (dual-core), Quad (quad-core), and Extreme (dual- or quad-core CPUs for enthusiasts) branches, during 2007.

The Core 2-branded CPUs included: "Conroe" and "Allendale" (dual-core for higher- and lower-end desktops), "Merom" (dual-core for laptops), "Kentsfield" (quad-core for desktops), and their variants named "Penryn" (dual-core for laptops), "Wolfdale" (dual-core for desktops) and "Yorkfield" (quad-core for desktops). Note: for the server and workstation "Woodcrest", "Clovertown", and "Tigerton" CPUs saw the Xeon brand.

The Core 2 branded processors featured the Virtualization Technology (except T52x0, T5300, T54x0, T55x0 with stepping "B2", E2xx0, E4x00 and E8190 models), Execute Disable Bit, and SSE3. Their Core microarchitecture introduced also SSSE3, Trusted Execution Technology, Enhanced SpeedStep, and Active Management Technology (iAMT2). With a Thermal Design Power (TDP) of up to only 65W, the Core 2 dual-core Conroe consumed only half the power of less capable, but also dual-core Pentium D-branded desktop chips with a TDP of up to 130W (a high TDP requires additional cooling that can be noisy or expensive).

The Kentsfield core

The Kentsfield released on November 2, 2006, was the first Intel desktop quad-core CPU branded Core 2 (and Xeon for lower-end servers and workstations). The top-of-the-line Kentsfields were Core 2 Extreme models numbered QX6xx0, while the mainstream ones branded Core 2 Quad were numbered Q6xx0. All of them featured two 4MB L2 caches. The mainstream Core 2 Quad Q6600, clocked at 2.4GHz, was launched on January 8, 2007 at US$851 (reduced to US$530 on April 7, 2007). July 22, 2007 marked the release of the Q6700, and Extreme QX6850 Kentsfields at US$530 and US$999 respectively along with a further price reduction of the Q6600 to US$266.

Analagous to the Pentium D branded CPUs, the Kentsfields comprised two separate silicon dies (each equivalent to a single Core 2 duo) on one MCM. This resulted in lower costs but lesser share of the bandwidth from each of the CPUs to the northbridge than if the dies were each to sit in separate sockets as was the case for example with the AMD Quad FX platform. Also, as might be predicted from the two-die MCM configuration, the max power consumption (TDP) of the Kentsfield (QX6800 - 130W, QX6700 - 130W, Q6600 - 95W) had been found to be double that of its similarly clocked Core 2 Duo counterpart.

Source: Wikipedia, the free encyclopedia.