The day we've been waiting for since the past couple of months has finally arrived. AMD, which pioneered DirectX 11 compliant PC consumer graphics, is out with its second-generation Radeon HD 6800 DirectX 11 architecture, codenamed Northern Islands. The company has enjoyed a 6 month head-start into the race for DirectX 11 graphics hardware market dominance, which also reflected in both growth of market-share, and domination in sales. The time passed by also allowed AMD to refine and fine-tune its architecture to better suit the existing 40 nm silicon fabrication process, by promising to churn out higher performance per Watt and performance per mm² of die-area (plays an important role in product pricing), compared to the previous-generation Evergreen architecture.The architecture of the Radeon HD 6870 also refines and expands on the product's feature-set, giving the GPU an even bigger role to play in today's PC than simply rendering 3D graphics: that's accelerating smooth and crystal-clear high-definition video, and getting into CPU territory, by number-crunching for applications at a much more parallel scale than multicore processors.The HD 6870 and HD 6850 products also mark a fundamental shift in AMD's approach to the market. Until now, the Radeon HD x800 series (such as HD 3800 series, HD 4800 series, and HD 5800 series) is regarded as that class of SKUs that give you the highest single-GPU performance possible for the prevalent architecture. But now, AMD has restructured its nomenclature in a big way.AMD bought ATI Technology back in 2006, yet it allowed ATI to remain as a brand name, since it has quite some market value to lead the graphics products, as its parent company moved through a rough patch on many fronts. Later, in a more stable environment, with two successive GPU series, the Radeon HD 4000 series and Radeon HD 5000 series, doing very well in the market, the company was able to gradually create a situation where "Radeon" became a bigger brand name than "ATI", at least that's what AMD argues, and hence has done away with "ATI" completely. So say hello to the first AMD-branded graphics processorSince the time of the Radeon 9600 XT and GeForce FX 5700 series, there has always been a $250-ish price-point which was very rigid, and held the reins of the "mid-range". Later, with increase in competitiveness between ATI and NVIDIA; product development cycle sped up, leading to a broadening of that mid-range spectrum, which then took over as a vast group of price-points starting from $100, all the way up to $250.Fast forward to Radeon HD 4000 series, AMD noticed quite some vacuum to fill between its $90 Radeon HD 4670, and the Radeon HD 4850, which at the former's launch was priced at $100, twice as much, there really was scope for something in the between since GeForce 9800 GT was having a party. Hence it created the Radeon HD 4700 series, which incidentally is also the first 40 n