Kentsfield (microprocessor)

Last updated
Core 2 Q6600 G0.JPG
Intel Core 2 Quad Kentsfield Q6600
General information
CPUID code06Fx
Product code80562
Max. CPU clock rate 2133 Mhz to 3000 Mhz
FSB speeds1066 MT/s to 1333 MT/s
L2 cache2x4 MiB
Architecture and classification
ApplicationDesktop, UP Server
Microarchitecture Core
Instruction set x86-64
Physical specifications
  • 4
Products, models, variants
Brand name(s)

Kentsfield is the code name of the first Intel desktop quad core [1] CPU branded Core 2 (and Xeon for lower-end servers and workstations), released on November 2, 2006. 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 4 MB L2 caches. The mainstream 65 nanometer Core 2 Quad Q6600, clocked at 2.4 GHz, 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. [2] Both Kentsfield and Kentsfield XE use product code 80562.



ProcessorBrand nameModel (list)CoresL2 cacheSocketTDP
Kentsfield Xeon 32xx 42x4 MiB LGA 775 95-105 W
Kentsfield Core 2 Quad Q6xxx 42x4 MiBLGA 77595-105 W
Kentsfield XE Core 2 Extreme QX6xxx 42x4 MiBLGA 775130 W


Analogous to the Pentium D branded CPUs, the Kentsfields comprise two separate silicon dies (each equivalent to a single Core 2 duo) on one MCM. [3] This results 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 is the case for example with the AMD Quad FX platform. [4] Also, as might be predicted from the two-die MCM configuration, the max power consumption (TDP) of the Kentsfield (QX6800 - 130  watts, [5] QX6700 - 130 W, [6] Q6600 - 105 W [7] ) has been found to be double that of its similarly clocked Core 2 Duo counterpart.

The multiple cores of the Kentsfield mostly benefits applications that can easily be broken into a small number of parallel threads (such as audio and video transcoding, data compression, video editing, 3D rendering and ray-tracing). To take a specific example, multi-threaded games such as Crysis and Gears of War which must perform multiple simultaneous tasks such as AI, audio and physics benefit from the quad-core CPUs. [8] In such cases, the processing performance may increase relative to that of a single-CPU system by a factor approaching the number of CPUs. This should, however, be considered an upper limit as it presupposes the user-level software is well-threaded. To return to the above example, some tests have demonstrated that Crysis fails to take advantage of more than two cores at any given time. [9] On the other hand, the impact of this issue on broader system performance can be significantly reduced on systems which frequently handle numerous unrelated simultaneous tasks such as multi-user environments or desktops which execute background processes while the user is active. There is still, however, some overhead involved in coordinating execution of multiple processes or threads and scheduling them on multiple CPUs which scales with the number of threads/CPUs. Finally, on the hardware level there exists the possibility of bottlenecks arising from the sharing of memory and/or I/O bandwidth between processors.

Kentsfield XE

The first Kentsfield XE, named Core 2 Extreme QX6700 (product code 80562) and clocked at 2.67 GHz, was released on November 2, 2006, at US$999. [10] [11] [12] [13] [14] January 4, 2008, marks its discontinuation. [15] It featured the Kentsfield XE core, and complemented the Core 2 Extreme X6800 dual-core processor based on the Conroe XE core. Like their dual core Extreme predecessors, CPUs with the Kentsfield XE core had unlocked multipliers.

The Core 2 Extreme QX6800 clocked at 2.93 GHz was released on April 8, 2007, at US$1,199. It had a 130  W TDP thermal envelope, and was intended for high end OEM-only systems. [16]

The Core 2 Extreme QX6850 clocked at 3.0 GHz was launched on July 22, 2007, at US$999. It featured a faster 1333 MT/s FSB. Simultaneously, the previously available Extreme QX6700 was reduced in price.

The dual-core desktop version of Kentsfield is Conroe, the server versions of Kentsfield are the dual-processor Clovertown (Xeon 53xx) and the multi-processor Tigerton (Xeon 73xx).


Kentsfield was subsequently replaced by the 45 nm Yorkfield processor.

Related Research Articles

Pentium 4 is a brand by Intel for an entire series of single-core CPUs for desktops, laptops and entry-level servers. The processors were shipped from November 20, 2000, until August 8, 2008. The production of Netburst processors was active from 2000 until May 21, 2010.


Xeon is a brand of x86 microprocessors designed, manufactured, and marketed by Intel, targeted at the non-consumer workstation, server, and embedded system markets. It was introduced in June 1998. Xeon processors are based on the same architecture as regular desktop-grade CPUs, but have advanced features such as support for ECC memory, higher core counts, support for larger amounts of RAM, larger cache memory and extra provision for enterprise-grade reliability, availability and serviceability (RAS) features responsible for handling hardware exceptions through the Machine Check Architecture. They are often capable of safely continuing execution where a normal processor cannot due to these extra RAS features, depending on the type and severity of the machine-check exception (MCE). Some also support multi-socket systems with two, four, or eight sockets through use of the Quick Path Interconnect (QPI) bus.

The Pentium D brand refers to two series of desktop dual-core 64-bit x86-64 microprocessors with the NetBurst microarchitecture, which is the dual-core variant of Pentium 4 "Prescott" manufactured by Intel. Each CPU comprised two dies, each containing a single core, residing next to each other on a multi-chip module package. The brand's first processor, codenamed Smithfield, was released by Intel on May 25, 2005. Nine months later, Intel introduced its successor, codenamed Presler, but without offering significant upgrades in design, still resulting in relatively high power consumption. By 2004, the NetBurst processors reached a clock speed barrier at 3.8 GHz due to a thermal limit exemplified by the Presler's 130 watt thermal design power. The future belonged to more energy efficient and slower clocked dual-core CPUs on a single die instead of two. The final shipment date of the dual die Presler chips was August 8, 2008, which marked the end of the Pentium D brand and also the NetBurst microarchitecture.

The Intel Core microarchitecture is a multi-core processor microarchitecture unveiled by Intel in Q1 2006. It is based on the Yonah processor design and can be considered an iteration of the P6 microarchitecture introduced in 1995 with Pentium Pro. High power consumption and heat intensity, the resulting inability to effectively increase clock speed, and other shortcomings such as an inefficient pipeline were the primary reasons why Intel abandoned the NetBurst microarchitecture and switched to a completely different architectural design, delivering high efficiency through a small pipeline rather than high clock speeds. The Core microarchitecture initially did not reach the clock speeds of the NetBurst microarchitecture, even after moving to 45 nm lithography. However after many generations of successor microarchitectures which used Core as their basis, Intel managed to eventually surpass the clock speeds of Netburst with the Devil's Canyon microarchitecture reaching a base frequency of 4 GHz and a maximum tested frequency of 4.4 GHz using 22 nm lithography.

Multi-core processor Microprocessor with more than one processing unit

A multi-core processor is a computer processor on a single integrated circuit with two or more separate processing units, called cores, each of which reads and executes program instructions. The instructions are ordinary CPU instructions but the single processor can run instructions on separate cores at the same time, increasing overall speed for programs that support multithreading or other parallel computing techniques. Manufacturers typically integrate the cores onto a single integrated circuit die or onto multiple dies in a single chip package. The microprocessors currently used in almost all personal computers are multi-core.

Intel Core 2

Intel Core 2 is the processor family encompassing a range of Intel's consumer 64-bit x86-64 single-, dual-, and quad-core microprocessors based on the Core micro-architecture. The single- and dual-core models are single-die, whereas the quad-core models comprise two dies, each containing two cores, packaged in a multi-chip module. The Core 2 range was the last flagship range of Intel desktop processors to use a front-side bus.


Pentium is a brand used for a series of x86 architecture-compatible microprocessors produced by Intel since 1993. In their form as of November 2011, Pentium processors are considered entry-level products that Intel rates as "two stars", meaning that they are above the low-end Atom and Celeron series, but below the faster Intel Core lineup, and workstation Xeon series.

The AMD Quad FX platform is an AMD platform targeted at enthusiasts which allows users to plug two Socket F Athlon 64 FX or 2-way Opteron processors (CPUs) into a single motherboard for a total of four physical cores. This is a type of dual processor setup, where two CPUs are installed on a motherboard to increase computing power. The major difference between the platform and past dual processor systems like Xeon is that each processor has its own dedicated memory stores. The Quad FX platform also has HyperTransport capability targeted toward consumer platforms.

LGA 771

LGA 771, also known as Socket J, is a CPU interface introduced by Intel in 2006. It is used in Intel Core microarchitecture and NetBurst microarchitecture(Dempsey) based DP-capable server processors, the Dual-Core Xeon is codenamed Dempsey, Woodcrest, and Wolfdale and the Quad-Core processors Clovertown, Harpertown, and Yorkfield-CL. It is also used for the Core 2 Extreme QX9775.

Intel's Skulltrail is an enthusiast gaming platform that was released on February 19, 2008. It is based on the company's 5400 "Seaburg" workstation chipset. The primary difference between Skulltrail and Intel's current and past enthusiast chipsets is a dual CPU socket design that allows two processors to operate on the same motherboard. Therefore, Skulltrail can operate eight processing cores on one system. The platform supports two Core 2 Extreme QX9775 processors, which operate at 3.2 GHz.

Haswell (microarchitecture) Intel processor microarchitecture

Haswell is the codename for a processor microarchitecture developed by Intel as the "fourth-generation core" successor to the Ivy Bridge. Intel officially announced CPUs based on this microarchitecture on June 4, 2013, at Computex Taipei 2013, while a working Haswell chip was demonstrated at the 2011 Intel Developer Forum. With Haswell, which uses a 22 nm process, Intel also introduced low-power processors designed for convertible or "hybrid" ultrabooks, designated by the "Y" suffix.

Conroe (microprocessor)

Conroe is the code name for many Intel processors sold as Core 2 Duo, Xeon, Pentium Dual-Core and Celeron. It was the first desktop processor to be based on the Core microarchitecture, replacing the NetBurst microarchitecture based Cedar Mill processor. It has product code 80557, which is shared with Allendale and Conroe-L that are very similar but have a smaller L2 cache. Conroe-L has only one processor core and a new CPUID model. The mobile version of Conroe is Merom, the dual-socket server version is Woodcrest, and the quad-core desktop version is Kentsfield. Conroe was replaced by the 45 nm Wolfdale processor.

Yorkfield is the code name for some Intel processors sold as Core 2 Quad and Xeon. In Intel's Tick-Tock cycle, the 2007/2008 "Tick" was Penryn microarchitecture, the shrink of the Core microarchitecture to 45 nanometers as CPUID model 23, replacing Kentsfield, the previous model.

Bloomfield (microprocessor) Code name for Intel high-end desktop processors sold as Core i7-9xx and Xeon 35xx., replacing the earlier Yorkfield processors

Bloomfield is the code name for Intel high-end desktop processors sold as Core i7-9xx and single-processor servers sold as Xeon 35xx., in almost identical configurations, replacing the earlier Yorkfield processors. The Bloomfield core is closely related to the dual-processor Gainestown, which has the same CPUID value of 0106Ax and which uses the same socket. Bloomfield uses a different socket than the later Lynnfield and Clarksfield processors based on the same 45 nm Nehalem microarchitecture, even though some of these share the same Intel Core i7 brand.

Intel Core Brand name that Intel uses for various mid-range to high-end consumer and business microprocessors

Intel Core are streamlined midrange consumer, workstation and enthusiast computers central processing units (CPU) marketed by Intel Corporation. These processors displaced the existing mid- to high-end Pentium processors at the time of their introduction, moving the Pentium to the entry level, and bumping the Celeron series of processors to the low end. Identical or more capable versions of Core processors are also sold as Xeon processors for the server and workstation markets.

LGA 2011

LGA 2011, also called Socket R, is a CPU socket by Intel. Released on November 14, 2011, it replaces Intel's LGA 1366 and LGA 1567 in the performance and high-end desktop and server platforms. The socket has 2011 protruding pins that touch contact points on the underside of the processor.

Skylake (microarchitecture)

Skylake is the codename used by Intel for a processor microarchitecture that was launched in August 2015 succeeding the Broadwell microarchitecture. Skylake is a microarchitecture redesign using the same 14 nm manufacturing process technology as its predecessor, serving as a "tock" in Intel's "tick–tock" manufacturing and design model. According to Intel, the redesign brings greater CPU and GPU performance and reduced power consumption. Skylake CPUs share their microarchitecture with Kaby Lake, Coffee Lake, Cannon Lake, Whiskey Lake, and Comet Lake CPUs.

Broadwell (microarchitecture)

Broadwell is the fifth model generation of Intel Processor. It's Intel's codename for the 14 nanometer die shrink of its Haswell microarchitecture. It is a "tick" in Intel's tick–tock principle as the next step in semiconductor fabrication. Like some of the previous tick-tock iterations, Broadwell did not completely replace the full range of CPUs from the previous microarchitecture (Haswell), as there were no low-end desktop CPUs based on Broadwell.


  1. "Intel Clovertowns step up, reduce power". TG Daily. Archived from the original on 2007-09-11. Retrieved 2007-09-05.
  2. "Intel Q3's Prices Revealed: 70% off to Intel C2Q Q6600". HKEPC Hardware. Archived from the original on 2007-03-15. Retrieved 2007-03-16.
  3. "Intel Kentsfield Preview". X-bit labs. Archived from the original on 2006-11-05. Retrieved 2006-09-29.
  4. "AMD's Quad FX platform: AMD decides to socket to 'em". The Tech Report. Retrieved 2007-06-11.
  5. "Overindulge Yourself with QX6800: Not Your Plain Vanilla System!". Tom's Hardware. Retrieved 2007-06-11.
  6. "Intel quad-core QX6700 reaches system builders". TG Daily. Archived from the original on 2007-09-26. Retrieved 2007-06-11.
  7. "Intel® Core™2 Quad Processor Q6600". Intel Ark. Intel.
  8. "Crysis - Confirmed Runs Best on Quad Core and 64 Bit OS". Tom's Hardware. Retrieved 2007-08-28.
  9. "No Quad Core Scaling in Crysis?". Extreme Tech. Retrieved 2008-03-09.
  10. "Intel's Core 2 Extreme QX6700: The Multi-core Era Begins". AnandTech. Retrieved 2006-11-11.
  11. "Intel Core 2 Extreme QX6700". Bit-Tech. Archived from the original on 2006-12-15. Retrieved 2006-11-11.
  12. ""Kentsfield" to Debut at 2.66 GHz". DailyTech. Archived from the original on 2006-10-21. Retrieved 2006-09-29.
  13. "The Quad Squad". CNET. Retrieved 2006-11-12.
  14. "Intel "Kentsfield" Named Core 2 Quad". DailyTech. Archived from the original on 2007-09-30. Retrieved 2006-09-29.
  15. "Intel already phasing out first quad-core CPU". TG Daily. Archived from the original on 2007-09-13. Retrieved 2007-09-07.
  16. "Overindulge Yourself with QX6800: Not Your Plain Vanilla System!". Tom's Hardware. Retrieved 2007-06-11.