I must admit Im getting pretty tired with all these chipset numbers floating around. Dont get me wrong, something new in the chipset line is always a good thing; nevertheless, it would be better if AMD decided to use names to designate its chipsets. INTEL seems to have gotten the idea and applies it right. Until AMD provides some names, the RDxxx numbering will have to do.
RD790 is a future Ati chipset with integrated DX10 capable graphics. The IGP will probably come in 2007 and should bring some interesting features to the value motherboard segment. For example, it will support no less than 52 PCIE lanes. This is enough to have three physical PCIE 16X slots and a single 4X one. I guess that AMD thinks of physics processing too because this is the only domain where a 3rd graphics PCIE is needed. In any case, the product sounds really cool especially if you take into account that its a value oriented IGP.
The chipset also has HTX support which will allow you to plug an additional add-in card that will bring future processor and memory support. This avoids draining bandwidth from the chipset and is done using Hyper Transport architecture. Nice addition to an already pretty impressive motherboard.
The RD790 is also Hyper Transport 3.0 compatible and that means it will work with new AM2+ CPUs that will also support HTT 3.0. The board is said support dual gigabit LAN and it will have its own cache memory. We dont know much about the cache integrated into the motherboard, but it will have a positive impact on latencies and bandwidth.