Architecture behind the 600i Series
Before we take a look at our first 600i series board, we want to have a look at the three chipsets that nVidia has in its line-up for the Intel platform. They are labelled at 680i at high-end, 650i SLI at the mid range and at the more mainstream end, the 650 Ultra.
Here we have the block diagrams for all chipsets - they share a lot of the features with minor differences between each variant. Our focus today is the 680i chipset.
The 680i is aimed at the enthusiasts with a lot of detail going into the chipset. nVidia has changed the way we overclock on this chipset by allowing Asynchronous bus overclocking of not just the CPU from the PCI-E and PCI but all buses. On a 680i motherboard, you can set your FSB independently of the memory bus speed, PCI-E, PCI and SATA clock speeds. nVidia attempted this in their nForce 4 Intel Edition chipsets but it didn't work too well - this time nVidia claim to have it working with support up to 1200MHz SLI Ready DDR-2 modules.
SLI also makes its comeback for Intel with the use of the 680i MCP. One of the two full-speed PCI Express x16 slots is routed through the Northbridge or SPP. The second PCI Express x16 slot resides on the MCP, like it has done with the 590 AMD series chipset. Hyper Transport links at 2000MHz connect the SPP to the MCP so there is no worry about a shortage of bandwidth for communication. Link boost technology also makes sure you get even more out of your SLI setup.
When you have two graphics cards in SLI, the SPP to MCP link is overclocked by 25% as well as the SPP PCI Express x16 and MCP PCI Express x16 lanes. This ensures that there is enough bandwidth to keep your SLI rig happy and provide a handy performance boost.
The 680i SPP contains two additional PCI Express lanes that can be used by expansion cards or on motherboard PCI Express chips such as additional RAID controllers with the MCP supporting four PCI Express x1 lanes for general use - in all, it is more than you will ever need at this stage of the game.
The 680i MCP has an additional 8 PCI Express lanes that are routed to a third PCI Express x16 slot. This is used to add an extra PCI Express graphics card for multiple monitor support or upcoming nVidia physics engine or even high-speed RAID controllers, for example.
Regarding media expansion, the 680i really has it all. nVidia has played down the IDE setup now (like Intel) with only a single IDE channel for two parallel ATA drives. The SATA ports are now expanded to 6 that are controlled by the MCP. These SATA ports can be configured into a large RAID array depending on your needs. Natively the 680i MCP supports nVidia Dual Net technology with two Gigabit Ethernet controllers integrated to the system supporting Fast packet and TCP/IP acceleration for faster interface with the LAN as well as lower CPU utilisation.