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 (computing), processor, is the electronic circuitry that executes Instruction (computing), instructions comprising a computer program. The CPU per ...

(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, joining it with another functional core on one die, 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, whic ...

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. 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 The thermal design power (TDP), sometimes called thermal design point, is the maximum amount of heat generated by a computer chip or component (often a CPU, GPU or system on a chip) that the cooling system in a computer is designed to dissipate ...

(TDP) of 45

Watt The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James ...

(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 Software is a set of computer programs and associated software documentation, documentation and data (computing), data. This is in contrast to Computer hardware, hardware, from which the system is built and which actually performs the work. ...

threads at the same time. The ability of processors to execute multiple threads simultaneously is called thread-level parallelism (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 A workstation is a special computer designed for technical or scientific applications. Intended primarily to be used by a single user, they are commonly connected to a local area network and run multi-user operating systems. The term ''workstat ...

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 An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also i ...

scheduling A schedule or a timetable, as a basic time-management tool, consists of a list of times at which possible tasks, events, or actions are intended to take place, or of a sequence of events in the chronological order in which such things are ...

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

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...

s. The 1 MB L2 cache 90 nm Athlon 64 X2 processor is 219 mm² in size with 243 million

s whereas its 1 MB L2 cache 90 nm Athlon 64 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 Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ta ...

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 p ...

, 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, Extended 3DNow!, SSE, SSE2,

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 techn ...

NX Bit The NX bit (no-execute) is a technology used in CPUs to segregate areas of memory for use by either storage of processor instructions or for storage of data, a feature normally only found in Harvard architecture processors. However, the NX bit i ...

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. Av ...

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 Apri ...

(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 pr ...

: 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, Extended 3DNow!, SSE, SSE2,

(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 *

: 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, Extended 3DNow!, SSE, SSE2,

, AMD-V * Socket AM2,

(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 *

: 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, Extended 3DNow!, SSE, SSE2,

, AMD-V * Socket AM2,

(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 *

: 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 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, Extended 3DNow!, SSE, SSE2,

, AMD-V * Socket AM2,

(1000 MHz, HT1000) * VCore: 1.15–1.20 V * Die size: 118 mm² * Power use ( TDP): 45 Watt * First release: October, 2007 *

: 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, SSE, SSE2,

, SSE4a, Enhanced 3DNow!,

NX bit The NX bit (no-execute) is a technology used in CPUs to segregate areas of memory for use by either storage of processor instructions or for storage of data, a feature normally only found in Harvard architecture processors. However, the NX bit i ...

, AMD-V *

Socket AM2+ Socket AM2+ is a CPU socket, which is the immediate successor to Socket AM2 that is used by several AMD processors such as Athlon 64 X2. Socket AM2+ is a mid-migration from Socket AM2 to Socket AM3 and both AM2+ and AM2 socket CPUs and mothe ...

(1800 MHz, HT3.0) * VCore: 1.05–1.25 V * Die size: 288 mm² * Power use: ( TDP): 95 Watt * First release: December 15, 2008 *

: 2300–2800 MHz ** 6500BE: 2300 MHz ** 7450: 2400 MHz ** 7550: 2500 MHz ** 7750BE: 2700 MHz ** 7850BE: 2800 MHz

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 o ...

Duo
AMD Athlon 64 Power and Thermal Data Sheet site (PDF)
{{AMD processors Advanced Micro Devices x86 microprocessors

Multithreading

Manufacturing costs

Features

CPU cores

Athlon 64 X2

Manchester (90 nm SOI)

Toledo (90 nm SOI)

Windsor (90 nm SOI)

Brisbane (65 nm SOI)

Athlon X2

Brisbane (65 nm SOI)

Kuma (65 nm SOI)

See also

References

External links