According to Intel, 25 to 40% of the CPU load in a game is linked to Direct3D and the graphics driver...
Over the course of various tests designed to observe this employment of quad-cores we came to the conclusion that there was one parameter that had a great deal more impact that expected: the graphics card, or rather, its driver.


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AMD has confirmed that the current drivers were not fully optimized for using quad core. This optimization should arrive during the first quarter of 2009 with new Catalyst drivers.
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