Intel and AMD have both been touting their capabilities in the multi-core race. Each semiconductor company has been showing four core, six core, and even eight core CPUs in their bids to impress the buying public. Decreased manufacturing costs due to smaller process geometries means that they can make these multi-core CPUs cheaply, but still charge large markups for these extra cores.

Unfortunately, Windows XP and Windows Vista don't handle all these cores efficiently. Most software is still single-threaded, which means often means that only two or three cores are fully utilized, if that. Multi-threaded games and software that is designed for four or more cores is on its way, but right now dual core processors are the way to go for most users.

This has been reflected in each company's sales strategies and their successes. Although Intel talks a lot about quad-core CPUs, over eighty percent of Intel's sales are dual core or single core CPUs. AMD, on the other hand, has bet heavily on quad-core CPUs with the original Phenom launch and now the Phenom II series of CPUs. Unfortunately for AMD, Intel's Core 2 Duo lineup is still incredibly popular, as consumers are choosing higher-clocked dual core CPUs versus AMD's quad-cores.

AMD has been working hard on their 45nm Silicon-On-Insulator (SOI) transition, and they are now ready to take on Intel in the mainstream dual core marketplace. AMD is launching two new Phenom II X2 dual core processors, as well as a more affordable Athlon II X2 dual core processor.

The AMD Athlon II X2 250 has two cores running at 3GHz with a 65W Thermal Design Power (TDP), a reduction of 30W from the Athlon X2 CPUs built on the 65nm process. It has 2MB of L2 cache, but will not have any L3 cache in order to differentiate it from the Phenom II X2 CPUs. It is manufactured using the AM3 package and designed for DDR3, but will use AM2+ motherboards with DDR2. Memory support includes DDR2 DIMMs up to 800MHz (PC2-6400) and DDR3 DIMMS up to 1066MHz (PC3-8500). AMD did this specifically to reduce the upgrade costs for its customers who don't want to change their platform completely. All that is needed is a BIOS upgrade from the motherboard manufacturer.

The Phenom II X2 550 Black Edition runs at 3.1GHz, but the multiplier is unlocked. Each core will have 512KB of L2 cache, but will have access to a large 6MB L3 cache. It will have an 80W TDP and use the AM3 socket. A Phenom II X2 545 clocked at 3GHz is supposed to come later with a 65W TDP. Both will support DDR2 DIMMs up to 1066MHz (PC2-8500) and DDR3 DIMMS up to 1333MHz (PC3-10600).

Key to AMD's success will be pricing and positioning. Instead of going for Intel's high end dual core processors such as the top selling Core 2 Duo E8400, AMD is positioning the Phenom II X2 550 Black Edition at $102 against the Intel Core 2 Duo E7400. Likewise, the Athlon II X2 250 will be priced at $87, against the Core 2 Duo E5400 at $113.

Higher end models such as the Phenom II X3 720 at $125 and the Phenom II X4 810 at $175 will continue to compete against Intel's high-end dual core CPUS such as the Core 2 Duo E8400, which sells for $163.

All prices listed are either MSRP or OEM pricing. Street prices at retail stores and at online e-tailers are likely to be lower.