[citation][nom]Pixel13[/nom]@ And it is to laugh at your "Seasonic over Corsair AX"--guess who builds the Corsair AX?[/citation]
Without guessing, and according to Corsair, Corsair builds the AX series from the ground up, not Seasonic. Even if it was, Corsair makes better cables.
Asus Sabertooth X58 is specifically a 2xGPU gaming/overclocking mobo that beats the UD3R, or any X58 board, in these specific tasks. IMO, If you're not using a 3rd PCI-E slot and reducing lanes as this build, you can't do better.
Noctua was the heatsink recommended by Tom's in the gift guide.