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The Athlon 64 X2 is the first native dual-core
desktop A desktop traditionally refers to: * The surface of a desk (often to distinguish office appliances that fit on a desk, such as photocopiers and printers, from larger equipment covering its own area on the floor) Desktop may refer to various compu ...
central processing unit A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, a ...
(CPU) designed by
Advanced Micro Devices Advanced Micro Devices, Inc. (AMD) is an American multinational semiconductor company based in Santa Clara, California, that develops computer processors and related technologies for business and consumer markets. While it initially manufact ...
(AMD). It was designed from scratch as native dual-core by using an already multi-CPU enabled
Athlon 64 The Athlon 64 is a ninth-generation, AMD64-architecture microprocessor produced by Advanced Micro Devices (AMD), released on September 23, 2003. It is the third processor to bear the name ''Athlon'', and the immediate successor to the Athlon XP. T ...
, joining it with another functional core on one
die Die, as a verb, refers to death, the cessation of life. Die may also refer to: Games * Die, singular of dice, small throwable objects used for producing random numbers Manufacturing * Die (integrated circuit), a rectangular piece of a semicondu ...
, and connecting both via a shared dual-channel memory controller/north bridge and additional control logic. The initial versions are based on the E stepping model of the Athlon 64 and, depending on the model, have either 512 or 1024 KB of
L2 cache A CPU cache is a hardware cache used by the central processing unit (CPU) of a computer to reduce the average cost (time or energy) to access data from the main memory. A cache is a smaller, faster memory, located closer to a processor core, which ...
per core. The Athlon 64 X2 can decode instructions for Streaming SIMD Extensions 3 (
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
), except those few specific to Intel's architecture. The first Athlon 64 X2 CPUs were released in May 2005, in the same month as Intel's first dual-core processor, the
Pentium D Pentium D is a range of desktop 64-bit x86-64 processors based on the NetBurst microarchitecture, which is the dual-core variant of the Pentium 4 manufactured by Intel. Each CPU comprised two dies, each containing a single core, residing next to ...
. In June 2007, AMD released low-voltage variants of their low-end 65 nm Athlon 64 X2, named " Athlon X2". The Athlon X2 processors feature reduced thermal design power (TDP) of 45 Watt (W). The name was also used for K10 based budget CPUs with two cores deactivated.


Multithreading

The primary benefit of dual-core processors (like the Athlon 64 X2) over single-core processors is their ability to process more software threads at the same time. The ability of processors to execute multiple threads simultaneously is called
thread-level parallelism Task parallelism (also known as function parallelism and control parallelism) is a form of parallelization of computer code across multiple processors in parallel computing environments. Task parallelism focuses on distributing tasks—concurren ...
(TLP). By placing two cores on the same die, the X2 effectively doubles the TLP over a single-core Athlon 64 of the same speed. The need for TLP processing ability depends on the situation to a great degree, and some situations benefit from it far more than others. Some programs are currently written for only one thread, and thus cannot use the processing power of a second core. Programs often written with multiple threads and able to use dual-cores include many music and video encoding applications, and especially professional rendering programs. High TLP applications currently correspond to server and workstation situations more than the typical desktop. These applications can reach almost twice the performance of a single-core Athlon 64 of the same specifications. Multitasking also runs a sizable number of threads. Intense multitasking processes have sped up by considerably more than twice. This is mostly due to the high overhead caused by constantly switching threads, and could potentially be improved by adjustments to operating system scheduling code. In the consumer segment of the market, the X2 improves on the performance of the original Athlon 64, especially for multi-threaded software.


Manufacturing costs

Having two cores, the Athlon 64 X2 has an increased number of transistors. The 1 MB L2 cache 90 nm Athlon 64 X2 processor is 219 mm² in size with 243 million transistors whereas its 1 MB L2 cache 90 nm
Athlon 64 The Athlon 64 is a ninth-generation, AMD64-architecture microprocessor produced by Advanced Micro Devices (AMD), released on September 23, 2003. It is the third processor to bear the name ''Athlon'', and the immediate successor to the Athlon XP. T ...
counterpart is 103.1 mm² and has 164 million transistors. The 65 nm Athlon 64 X2 with only 512 KB L2 per Core reduced this to 118 mm² with 221 million transistors compared to the 65 nm Athlon 64 with 77.2 mm² and 122 million transistors. As a result, a larger area of silicon must be defect free. These size requirements necessitate a more complex
fabrication process Semiconductor device fabrication is the process used to manufacture semiconductor devices, typically integrated circuit (IC) chips such as modern computer processors, microcontrollers, and memory chips such as NAND flash and DRAM that are pres ...
, which further adds to the production of fewer functional processors per single silicon wafer. This lower yield makes the X2 more expensive to produce than the single-core processor. In the middle of June 2006 AMD stated that they would no longer make any non-FX Athlon 64 or Athlon 64 X2 models with 1 MB L2 caches. This led to only a small production number of the Socket-AM2 Athlon 64 X2 with 1 MB L2 cache per core, known as 4000+, 4400+, 4800+, and 5200+. The Athlon 64 X2 with 512 KB per core, known as 3800+, 4200+, 4600+, and 5000+, were produced in far greater numbers. The introduction of the F3 stepping then saw several models with 1 MB L2 cache per core as production refinements resulted in an increased yield.


Features

CPU features table


CPU cores


Athlon 64 X2


Manchester (90 nm SOI)

* Silicon on insulator (SOI) * CPU stepping: E4 * L1 cache: 64 + 64 KB (data + instructions), per core * L2 cache: 256, 512 KB full speed, per core *
MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...
, Extended
3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...
, SSE, SSE2,
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
,
AMD64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging m ...
,
Cool'n'Quiet AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technolog ...
, NX Bit *
Socket 939 Socket 939 is a CPU socket released by AMD in June 2004 to supersede the previous Socket 754 for Athlon 64 processors. Socket 939 was succeeded by Socket AM2 in May 2006. It is the second socket designed for AMD's AMD64 range of processors. Avai ...
,
HyperTransport HyperTransport (HT), formerly known as Lightning Data Transport, is a technology for interconnection of computer processors. It is a bidirectional serial/parallel high-bandwidth, low- latency point-to-point link that was introduced on April 2 ...
(1000 MHz, HT1000) * VCore: 1.35–1.4 V * Power use ( TDP): 89 Watt * First release: 1 August 2005 *
Clock rate In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the p ...
: 2000–2400 MHz ** 256 KB L2 cache: *** 3600+: 2000 MHz ** 512 KB L2 cache: *** 3800+: 2000 MHz *** 4200+: 2200 MHz *** 4600+: 2400 MHz (110 Watt TDP)


Toledo (90 nm SOI)

* Silicon on insulator (SOI) * CPU stepping: E6 * L1 cache: 64 + 64 KB (data + instructions), per core * L2 cache: 512 or 1024 KB full speed, per core *
MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...
, Extended
3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...
, SSE, SSE2,
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
,
AMD64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging m ...
,
Cool'n'Quiet AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technolog ...
, NX Bit *
Socket 939 Socket 939 is a CPU socket released by AMD in June 2004 to supersede the previous Socket 754 for Athlon 64 processors. Socket 939 was succeeded by Socket AM2 in May 2006. It is the second socket designed for AMD's AMD64 range of processors. Avai ...
,
HyperTransport HyperTransport (HT), formerly known as Lightning Data Transport, is a technology for interconnection of computer processors. It is a bidirectional serial/parallel high-bandwidth, low- latency point-to-point link that was introduced on April 2 ...
(1000 MHz, HT1000) * VCore: 1.35–1.4 V * Power use ( TDP): ** 89 Watt: 3800+, 4200+ and 4400+ ** 110 Watt: 4400+, 4600+ and 4800+ * First release: 21 April 2005 *
Clock rate In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the p ...
: 2000–2400 MHz ** 512 KB L2 cache: *** 3800+: 2000 MHz *** 4200+: 2200 MHz *** 4600+: 2400 MHz ** 1024 KB L2 cache: *** 4400+: 2200 MHz *** 4800+: 2400 MHz


Windsor (90 nm SOI)

* Silicon on insulator (SOI) * CPU stepping: F2, F3 * L1 cache: 64 + 64 KB (data + instructions), per core * L2 cache: 256, 512 or 1024 KB full speed, per core *
MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...
, Extended
3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...
, SSE, SSE2,
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
,
AMD64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging m ...
,
Cool'n'Quiet AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technolog ...
, NX Bit,
AMD-V x86 virtualization is the use of hardware-assisted virtualization capabilities on an x86/x86-64 CPU. In the late 1990s x86 virtualization was achieved by complex software techniques, necessary to compensate for the processor's lack of hardware-as ...
*
Socket AM2 The Socket AM2, renamed from Socket M2 (to prevent using the same name as Cyrix MII processors), is a CPU socket designed by AMD for desktop processors, including the performance, mainstream and value segments. It was released on May 23, 2006, as ...
,
HyperTransport HyperTransport (HT), formerly known as Lightning Data Transport, is a technology for interconnection of computer processors. It is a bidirectional serial/parallel high-bandwidth, low- latency point-to-point link that was introduced on April 2 ...
(1000 MHz, HT1000) * VCore: 1.25–1.35 V * Power use ( TDP): ** 35 Watt (3800+ EE SFF) ** 65 Watt (3600+ to 5200+ EE) ** 89 Watt (3800+ to 6000+) ** 125 Watt (6000+ to 6400+) * First release: May 23, 2006 *
Clock rate In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the p ...
: 2000 MHz–3200 MHz ** 256 KB L2 cache: *** 3600+: 2000 MHz ** 512 KB L2 cache: (often mislabeled as ''Brisbane'' core) *** 3800+: 2000 MHz *** 4200+: 2200 MHz *** 4600+: 2400 MHz (F2&F3) *** 5000+: 2600 MHz (F2&F3) *** 5400+: 2800 MHz (F3) ** 1024 KB L2 cache: *** 4000+: 2000 MHz *** 4400+: 2200 MHz *** 4800+: 2400 MHz *** 5200+: 2600 MHz (F2&F3) *** 5600+: 2800 MHz (F3) *** 6000+: 3000 MHz (F3) *** 6400+: 3200 MHz (F3)


Brisbane (65 nm SOI)

* Silicon on insulator (SOI) * CPU stepping: G1, G2 * L1 cache: 64 + 64 KB (data + instructions), per core * L2 cache: 512 KB full speed, per core *
MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...
, Extended
3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...
, SSE, SSE2,
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
,
AMD64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging m ...
,
Cool'n'Quiet AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technolog ...
, NX Bit,
AMD-V x86 virtualization is the use of hardware-assisted virtualization capabilities on an x86/x86-64 CPU. In the late 1990s x86 virtualization was achieved by complex software techniques, necessary to compensate for the processor's lack of hardware-as ...
*
Socket AM2 The Socket AM2, renamed from Socket M2 (to prevent using the same name as Cyrix MII processors), is a CPU socket designed by AMD for desktop processors, including the performance, mainstream and value segments. It was released on May 23, 2006, as ...
,
HyperTransport HyperTransport (HT), formerly known as Lightning Data Transport, is a technology for interconnection of computer processors. It is a bidirectional serial/parallel high-bandwidth, low- latency point-to-point link that was introduced on April 2 ...
(1000 MHz, HT1000) * VCore: 1.25–1.35 V * Die size: 126 mm² * Power use ( TDP): 65 or 89 Watt * First release: Dec 5, 2006 *
Clock rate In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the p ...
: 1900 MHz–3100 MHz ** 3600+: 1900 MHz (G1) ** 3800+: 2000 MHz ** 4000+: 2100 MHz ** 4200+: 2200 MHz (G1&G2) ** 4400+: 2300 MHz (G1&G2) ** 4600+: 2400 MHz (G2) ** 4800+: 2500 MHz (G1&G2) ** 5000+: 2600 MHz (G1&G2) ** 5200+: 2700 MHz (G1&G2) ** 5400+: 2800 MHz (G2) ** 5600+: 2900 MHz (G2) ** 5800+: 3000 MHz (G2) ** 6000+: 3100 MHz (G2)


Athlon X2

'64' was omitted from the name of the Brisbane 'BE' series; the 64-bit marketing campaign initiated by AMD became insignificant once essentially all consumer CPUs became
64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit CPUs and ALUs are those that are based on processor registers, address buses, or data buses of that size. A comput ...
processors.


Brisbane (65 nm SOI)

* Silicon on insulator (SOI) * CPU stepping: G2 * L1 cache: 64 + 64 KB (data + instructions), per core * L2 cache: 512 KB full speed, per core *
MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...
, Extended
3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...
, SSE, SSE2,
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
,
AMD64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging m ...
,
Cool'n'Quiet AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technolog ...
, NX Bit,
AMD-V x86 virtualization is the use of hardware-assisted virtualization capabilities on an x86/x86-64 CPU. In the late 1990s x86 virtualization was achieved by complex software techniques, necessary to compensate for the processor's lack of hardware-as ...
*
Socket AM2 The Socket AM2, renamed from Socket M2 (to prevent using the same name as Cyrix MII processors), is a CPU socket designed by AMD for desktop processors, including the performance, mainstream and value segments. It was released on May 23, 2006, as ...
,
HyperTransport HyperTransport (HT), formerly known as Lightning Data Transport, is a technology for interconnection of computer processors. It is a bidirectional serial/parallel high-bandwidth, low- latency point-to-point link that was introduced on April 2 ...
(1000 MHz, HT1000) * VCore: 1.15–1.20 V * Die size: 118 mm² * Power use ( TDP): 45 Watt * First release: October, 2007 *
Clock rate In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the p ...
: 1900 MHz–2600 MHz ** BE-2300: 1900 MHz (G2) ** BE-2350: 2100 MHz (G2) ** BE-2400: 2300 MHz (G2) ** BE-2450: 2500 MHz (G2) ** 4050e: 2100 MHz (G2) ** 4450e: 2300 MHz (G2) ** 4850e: 2500 MHz (G2) ** 5050e: 2600 MHz (G2)


Kuma (65 nm SOI)

* Chip harvests from Agena with two cores disabled * Silicon on insulator (SOI) *
AMD K10 The AMD Family 10h, or K10, is a microprocessor microarchitecture by AMD based on the K8 microarchitecture. Though there were once reports that the K10 had been canceled,
microarchitecture * CPU stepping: B3 * L1 cache: 64 + 64 KB (data + instructions), per core * L2 cache: 512 KB full speed, per core * L3 cache: 2 MB (shared) *
MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...
, SSE, SSE2,
SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...
, SSE4a, Enhanced
3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...
, NX bit,
AMD64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging m ...
,
Cool'n'Quiet AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technolog ...
,
AMD-V x86 virtualization is the use of hardware-assisted virtualization capabilities on an x86/x86-64 CPU. In the late 1990s x86 virtualization was achieved by complex software techniques, necessary to compensate for the processor's lack of hardware-as ...
* Socket AM2+,
HyperTransport HyperTransport (HT), formerly known as Lightning Data Transport, is a technology for interconnection of computer processors. It is a bidirectional serial/parallel high-bandwidth, low- latency point-to-point link that was introduced on April 2 ...
(1800 MHz, HT3.0) * VCore: 1.05–1.25 V * Die size: 288 mm² * Power use: ( TDP): 95 Watt * First release: December 15, 2008 *
Clock rate In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the p ...
: 2300–2800 MHz ** 6500BE: 2300 MHz ** 7450: 2400 MHz ** 7550: 2500 MHz ** 7750BE: 2700 MHz ** 7850BE: 2800 MHz


See also

*
List of AMD Athlon X2 processors The AMD Athlon X2 processor family consists of processors based on both the Athlon 64 X2 and the Phenom processor families. The original Athlon X2 processors were low-power Athlon 64 X2 ''Brisbane'' processors, while newer processors released in Q ...
*
List of AMD Athlon 64 processors The Athlon 64 microprocessor from Advanced Micro Devices (AMD) is an eighth-generation central processing unit (CPU). Athlon 64 is targeted at the consumer market. Features overview CPU features table Single-core desktop processors Athlon 6 ...
* List of AMD Athlon II processors *
List of AMD processors This article gives a list of AMD microprocessors, sorted by generation and release year. If applicable and openly known, the designation(s) of each processor's core (versions) is (are) listed in parentheses. For an overview over concrete product, y ...
* Parallel computing


References


External links


Athlon64 X2 product site

Comparison
with the
Intel Core Intel Core is a line of streamlined midrange consumer, workstation and enthusiast computer central processing units (CPUs) marketed by Intel Corporation. These processors displaced the existing mid- to high-end Pentium processors at the time ...
Duo
AMD Athlon 64 Power and Thermal Data Sheet site (PDF)
{{AMD processors Advanced Micro Devices x86 microprocessors