The Athlon 64 X2 is the first dual-core desktop CPU manufactured by AMD. It is essentially a processor consisting of two Athlon 64 cores joined together on one die with some additional control logic. The cores share one dual-channel memory controller, are based on the E-stepping model of Athlon 64 and, depending on the model, have either 512 or 1024 Kb of L2-Cache per core. The X2 is capable of decoding SSE3 instructions, so it can run and benefit from software optimizations that were previously only supported by Intel chips. This enhancement is not unique to the X2, and is also available in the recently released Venice and San Diego single core Athlon 64's.

For the end-user this means a significant increase in response and performance when running multiple applications simultaneously. The AMD Athlon™ 64 X2 Dual-Core processor outperforms the highest-performing AMD Athlon™ 64 4000+ single-core processor on multi-tasking benchmarks by up to 30%, according to the official press release. AMD officially started shipping the Athlon 64 X2 at Computex, on 1 June 2005.

In the middle of June 2006, AMD stated that they will no longer make any non-FX Athlon 64 or Athlon 64 X2 models with 1MB L2 caches. This was reported by Hardocp website. This means that only a small number of the Socket AM2 is being produced. Probably you will see at your local store only the 512KB L2 cache models: 3800+, 4200+, 4600+, and 5000+.

- AMD Athlon 64 X2 Features

Better Multi-Tasking Means Increased Office Productivity
Productivity in today’s workplace requires smooth, efficient and seamless multi-tasking. The AMD Athlon 64 X2 Dual-Core processor delivers TRUE multi-tasking, allowing users to switch from one program to another without pausing for the computer to catch up and reducing annoying processing pauses. The end result is an increase in office productivity performance of 22% on average.

Setting the Pace in Digital Media
Digital media software demands simultaneous processing of data streams, the perfect use for the incredible multi-tasking power of the AMD64 dual-core technology. Dual-core technology is like having two processors working together, each one taking care of different applications, so power-users actually experience greater performance when multiple applications are running. Digital media enthusiasts can usher in the next generation of digital media software for amazing high-definition video and photo editing, content creation, and audio mixing. With the AMD Athlon™ 64 X2 Dual-Core processor, your PC will perform up to 80% faster than a single-core AMD Athlon™ 64 4000+ processor on the latest power-hungry digital media software applications.

Smooth and Efficient Upgrades
Additionally, the elegant design of the AMD64 architecture allowed for the planning of dual-core processors from the ground up, which means that the AMD Athlon™ 64 X2 Dual-Core processor is designed to fit in the same 939-pin infrastructure as single-core processors. All that is required is a BIOS update, saving our partners the costs of redesigns and obsolete inventory.

All the Proven Benefits of AMD64 Technology
Enhanced Virus Protection with Windows® XP Service Pack 2
Enhanced Virus Protection is a feature of AMD64 technology. Enhanced Virus Protection feature in AMD64 processors, in conjunction with certain operating systems help to prevent the spread of certain viruses, like MSBlaster and Slammer, significantly reducing the cost and down-time associated with similar viruses and improving the protection of computers and personal information against certain PC viruses1.

AMD Athlon 64 Processor Architecture Performance
HyperTransport™ technology can increase overall system performance by removing I/O bottlenecks, increasing system bandwidth, and reducing system latency. A fully integrated DDR memory controller helps speed access to memory by offering the processor a direct connection to the main memory. As a result, end users can enjoy quicker application loading and extraordinary application performance.

Ready for the 64-bit future
Like all the processors in the AMD Athlon 64 family, the AMD Athlon 64 X2 Dual-Core processor is designed for people who want to stay at the forefront of technology and for those who depend on their PCs to keep them connected, informed, and entertained. Systems based on AMD Athlon 64 processors are able to deliver leading-edge performance for demanding productivity and entertainment software today and in the future.