Elite Bastards published a review of ASUS' high-end, nForce 780i-sporting Striker II Formula motherboard A quote from the article:

One of the main focuses of nForce 780i is the introduction of the nForce 200 chip, which brings PCI Express 2.0 support to this chipset alongside three full 16x PCI Express slots, allowing for the use of 3-way SLI with GeForce 8800 GTX and Ultra graphics boards. While it isn't really a big deal at this point in time, it's worth noting that only two of these three slots are PCI Express 2.0, with the third slot actually provided directly from the nForce 780i's MCP, and thus sporting PCI Express 1.1 only. To further confuse matters, the nForce 200 chip connects to the nForce 780i SLI MCP using a proprietary NVIDIA interface which gives it a bandwidth of 14.4 GB/sec - This is actually far less than the 32 GB/sec maximum bandwidth of which two 16x PCI Express 2.0 slots are capable. Thankfully, it's very unlikely that you'll ever actually run into bandwidth limitations along those lines in current applications.

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