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The ASUS P9X79 Pro comes with the required SLI bridges for both 2-WAY and 3-WAY SLI. The triple width GPU does fit both on the MOBO and in the case. The bottom GPU will also cover a good portion of the bottom edge headers, but there's enough room to 90-degree those header wires. No doubt the bottom GPU is hovering about finger width above the PSU, but that's enough for proper air flow.