Asus NV 780i Motherboard Sneak Peek - 3-Way SLI
This is the first NVIDIA nForce 780i board to hit our labs. Upon close inspection, it does look as though rumors that NVIDIA has bolted a Gen2 bridge (or switch perhaps) up to the 680i chipset, are fairly accurate, though the architecture merits a bit more analysis before casting judgment. The real question is, exactly what does the NF200 chip do in conjunction with NVIDIA's 680i Northbridge core (now dubbed 780i in conjunction with the NF200)? Is the new NF200 simply a PCI Express 2.0 fanout switch, taking 32 lanes of PCI Express 1.1 from the northbridge and distributing them down to the PEG slots with PCI Express 2.0 support? If this is the case, obviously since the "root complex" back at the Northbridge is PCIe 1.1 only, the slots will technically be "over-subscribing" the upstream links to the Northbridge since the PEG slots will have PCIe Gen 2 5GB/sec SerDes versus the 2.5GB/sec PCIe 1.1 link on the Northbridge. It could also be that NVIDIA has taken HyperTransport links from the Northbridge and utilized them with the NF200 chip as an HT to PCIe Gen2 bridge. Likely, it's the former architecture however, as we can clearly see here with the individual traces for each lane coming out of the Northbridge. We're digging in deeper here and have fired off a few questions to NVIDIA in this regard. We'll update this story as details come in.
As you'll see in the shots below, there is also a third X16 slot, for a full three slots of Gen2 PCI Express X16 connectivity and three-way SLI Graphics.
Finally, above you can see the new NVIDIA three-way SLI bridge connector board that is used to provide direct communications between the cards for graphics load-balancing. The new P5N-T Deluxe from Asus is obviously targeted to enthusiasts, with a highly integrated solution in a feature-rich offering. It will be interesting to see how the board performs with three GeForce 8800 GTX or Ultra cards in its slots and also what price-point this new NVIDIA infused gaming platform will weigh in. Stick around. We'll be answering that question in the weeks ahead.