AMD demoes PCIe 2.0 in action
 

AMD Hammerhead is a motherboard that features one Socket AM2+ for Agena/Kuma cores. It features two PCIe 2.0 slots and two regular full-sized PCIe 1.1 slots. If you take into account that PCIe 2.0 is backwards compatible with 1.1, you can see making the ground for a Quad Crossfire concept, that is probably going to debut with arrival of HD2400/2600 (RV610/630) and upcoming RV670 chips.

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