AMD and Intel have been extremely active on the desktop processor front through 2007, introducing both price drops and new products, and as a result, have totally transformed the market. Ultra high priced desktop processors are quickly turning into the dinosaurs of the market, as both companies trim the fat and offer powerful CPUs for a fraction of their introductory price. Product releases have also followed this pattern, and any new processors from AMD and Intel seem to have accepted this new market reality, and slipped into the existing price structure.
This type of intense price and product competition has yielded significant benefits to consumers, and the type of price-performance ratios you can receive today simply dwarfs anything in the past. AMD has been at the forefront of the price drop trend, and other than the new Athlon 64 X2 6400+, none of their desktop processor line is priced over $200. One real bright spot is the Athlon 64 X2 5600+, which not only offers top of the line mainstream performance, but has lower power and thermal specs, on par with the Athlon 64 X2 5000+ to 5400+ range.
The processor's basic specs remain intact, and the Athlon 64 X2 5600+ is simply a 2.8 GHz version of the 90nm Windsor core. This translates into 64K of L1 instruction and 64K of L1 data cache per core, for a total of 256KB of L1 cache, and an L2 configuration of 1MB of L2 data cache per core, or a total of 2MB of L2 cache. AMD still hasn't made the transition to 65nm for its higher-speed models, so the Athlon 64 X2 5600+ remains a 90nm part, but it does offer a lower power envelope compared to the Athlon 64 X2 6000+. This is also a Socket AM2 part, and features an integrated dual-channel memory controller that supports up to DDR2-800 speeds and a theoretical memory bandwidth of 12.8 GB/second.
The Athlon 64 X2 5600+ includes support for AMD64, HyperTransport, Enhanced Virus Protection, and AMD Virtualization technology, while many of its power and thermal specifications sit a level lower than the Athlon 64 X2 6000+ and 6400+. The Athlon 64 X2 5600+ offers a core voltage of 1.3V-1.35V, a thermal power rating of only 89W, a processor current of 65 A, and a transistor count of 227.4 million. This processor represents the highest clocked version of this mid-level power design, and once you move to the Athlon 64 X2 6000+ or higher, this jumps to a TDP of 125W and a 90.5 A processor current. The Athlon 64 X2 5600+ also supports AMD Cool'n'Quiet, and offers max power-saving specifications of 1.1V core voltage, 23.8 A current, 29.2W thermal power, and a 1.0 GHz ramped-down clock speed.
One major benefit of the Athlon 64 X2 5600+ is its "even" 14x clock generator and the ability to run at pure DDR2-800 speeds with 12.8 GB/s of memory bandwidth. This translates into a slightly higher memory speed and bandwidth compared to a processor with an "uneven" multiplier like the Athlon 64 X2 6000+, which runs at only 746 MHz and sports 11.9 GB/s of memory bandwidth. Even worse are the processors with fractional multipliers, like the 65nm Athlon 64 X2 4800+ (12.5x), which runs at only 714 MHz DDR and supplies just 11.4 GB/s of memory bandwidth. These may seem like small differences to some, but many enthusiasts seek out a true DDR2-800 Athlon 64 X2 processor in order to get the highest memory performance.