I'm thinking about getting this board and pairing it with a Noctua NH-U9S CPU cooler (which, by coincidence, is on ASUS's QVL for this board). Like most "tower" coolers though, it places the fan and airflow a good 3-4cm "above" the board, which means it wouldn't be blowing directly at the main VRM heat-sink (as oppose to something like the stock Intel cooler which blows at everything around it). Is there a potential issue here or am I overthinking it? Also, since I have no interest in lighting, would removing the plastic I/O shroud (which looks like it covers most of the main VRM heat sink anyway) be of benefit here?
Welcome to the ROG forum, you have good taste in choosing ROG. 🙂
You can leave the I/O shroud on and turn the cool looking RGB light(s) off in the bios on the Advanced tab - Onboard Devices configuration, it won't benefit much if at all removing it
The ROG boards are designed for overclocking and ASUS doesn't skimp on their heatsinks, as long as you have decent airflow in your case you don't need a fan blowing directly over them. You can even overclock and be safe, I'm using the Maximus IX Code and have my cpu overlocked to 5.2GHz with 1.44v with no fan blowing over the vrm's.
I imagine you'll be using the i7-8700k? If so and you plan on overclocking, look into delidding.