I currently run an i7 3770k overclocked with a H100 Watercooler . Really happy with performance. As to your MoBo choice , that rather depends on budget . I run a z77 sabretooth , a great gaming MoBo . It certainly wont hurt performance overclocking and watercooling , it all comes down to your budget . I would go for the biggest SSD you can , and try to squeeze your budget to up the memory to 16 gb . Good luck .
HTC U12 Plus review: Hands-on