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Athlon 64




The Athlon 64 (codenamed "ClawHammer", "Newcastle", "Winchester", "Venice", and "San Diego") represents AMD 's entry into the consumer 64-bit Microprocessor market, released on September 23 , 2003 . This processor implements the AMD64 architecture. It is AMD's first K8 eighth generation processor core for desktop and mobile computers.

There are three variants: ''Athlon 64'', ''Athlon 64 FX'', and the dual-core '' Athlon 64 X2 ''. The Athlon 64 FX is positioned as a hardware enthusiast product, always one speed step above the fastest Athlon 64. Although its clock rates are usually higher, all Athlon 64 FX processors are a single-core design with the exception of the Athlon 64 FX-60, which was released on January 10th of 2006. It is currently available on Socket 939 , with Socket AM2 support promised in the future. This release is analogous to that of the Athlon 64 FX-53, which was initially available at a time when Socket 939 had not yet been introduced; as such it was only made for the higher end Socket 940 platform, but saw a Socket 939 model at a later date. All of the Athlon 64 FX processors have their multipliers unlocked, and normal Athlon 64s have their multipliers unlocked downward (meaning that users can select any multipliers up to and including the factory-set default one). As an implementation of the AMD64 architecture, all Athlon 64 variants are able to run 32 bit X86 , 16 Bit , and AMD64 Code .




FEATURES

The Athlon 64 features an on-die memory controller, a feature not previously seen on x86 CPUs. Not only does this mean the controller runs at the same clock rate as the CPU itself, it also means the electrical signals have a shorter physical distance to travel compared to the old Northbridge interfaces. The result is a significant reduction in latency (response time) for access requests to main memory.

Translation Lookaside Buffer s (TLBs) have also been enlarged (40 4k/2M/4M entries in L1 cache, 512 4k entries), with reduced latencies and improved branch prediction, with four times the number of bimodal counters in the global history counter. This and other architectural enhancements, especially as regards SSE implementation, improve instruction per cycle ( IPC ) performance over the previous Athlon XP generation. To make this easier for consumers to understand, AMD has chosen to market the Athlon 64 using a PR Rating (Performance Rating) system, where the numbers roughly map to Pentium 4 performance equivalents, rather than actual clock speed.

Athlon 64 also features CPU speed throttling technology branded '' Cool'n'Quiet ''. When the user is running undemanding applications and the load on the processor is light, the processor's clock speed and voltage are reduced. This in turn reduces its peak power consumption (max TDP set at 89 W by AMD) to as low as 32 W ( Stepping C0, clock speed reduced to 800 MHz) or 22W (stepping CG, clock speed reduced to 1 GHz).

The No Execute Bit (NX Bit) supported by Windows XP Service Pack 2, Windows XP Professional x64 Edition, Windows Server 2003 x64 Edition, and Linux 2.6.8 and higher is also included, for improved protection from malicious buffer overflow security threats. Hardware-set permission levels make it much more difficult for malicious code to take control of the system. It is intended to make 64-bit computing a more secure environment.

The Athlon 64 CPUs have been produced with 130 nm and 90 nm SOI process technologies. All of the latest chips (Winchester, Venice and San Diego models) are on 90nm. The Venice and San Diego models also incorporate dual stress liner technology (an amalgamy of Strained Silicon and 'squeezed silicon', the latter of which is not actually a technology) co-developed with IBM.

As the memory controller is integrated onto the CPU die, there is no FSB for the system memory to base its speed upon. Instead, system memory speed is obtained from the following formula:

:{CPU multiplier\over DRAM divider} imes {CPU speed} = {DRAM Speed}


SOCKETS

  • 754 : The Athlon 64 value/budget line, 64-bit memory interface (Single-Channel)

  • s, and newer Athlon 64 FXs, 128-bit memory interface ( Dual-channel )

  • and old Athlon 64 FX, 128-bit memory interface - requires registered DDR memory

  • Socket F : Opteron. Yet to be Released (ETA 2006), 1207 Pins

  • Will replace Sockets 754 and 939 in 2006. 940 Pins (Not compatible with Socket 940) and will be the first AMD socket to use DDR2 SDRAM .


At the introduction of Athlon 64 in September 2003, only Socket 754 and Socket 940 (Opteron) were ready and available. The onboard memory controller was not capable of running unbuffered (non-registered) memory in dual-channel mode at the time of release; as a stopgap measure, they introduced the Athlon 64 on Socket 754, and brought out a non-multiprocessor version of the Opteron called the Athlon 64 FX, as a multiplier unlocked enthusiast part for Socket 940, comparable to Intel's Pentium 4 Extreme Edition for the high end market.

In June 2004, AMD released Socket 939 as the mainstream Athlon 64 with dual-channel memory interface, leaving Socket 940 solely for the server market (Opterons), and relegating Socket 754 as a value/budget line, for Semprons and slower versions of the Athlon 64. Eventually Socket 754 replaced Socket A for Semprons.


ATHLON 64 FX MODELS


Sledgehammer (130 nm SOI )

  • CPU-Stepping: C0, CG

  • L1-Cache: 64 + 64 KiB (Data + Instructions)

  • L2-Cache: 1024 KiB, fullspeed

  • MMX , Extended 3DNow! , SSE , SSE2 , AMD64

  • Socket 940 , 800 MHz HyperTransport (HT800)

  • Registered DDR-SDRAM required

  • VCore: 1.50/1.55 V

  • Power Consumption ( TDP ): 89 Watt max

  • First Release: September 23 , 2003

  • Clockrate: 2200 MHz (FX-51, C0), 2400 MHz (FX-53, C0 and CG)



Clawhammer (130 nm SOI)

  • CPU-Stepping: CG

  • L1-Cache: 64 + 64 KiB (Data + Instructions)

  • L2-Cache: 1024 KiB, fullspeed

  • MMX , Extended 3DNow! , SSE , SSE2 , AMD64

  • Socket 939 , 1000 MHz HyperTransport (HT1000)

  • VCore: 1.50 V

  • Power Consumption ( TDP ): 89 Watt (FX-55:104 Watt)

  • First Release: June 1 , 2004

  • Clockrate: 2400 MHz (FX-53), 2600 MHz (FX-55)



San Diego (90 nm SOI)



Toledo (90 nm SOI)

Dual-core CPU


ATHLON 64 MODELS


Clawhammer (130 nm SOI )



Newcastle (130 nm SOI)

Downlabeled Clawhammer with only 512KiB L2-Cache possible, too


Winchester (90 nm SOI)



Venice (90 nm SOI)



San Diego (90 nm SOI)



SEE ALSO



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