Looks like good, compatible choices, and great for gaming with that 1080ti. Custom water loop cooling is a great choice and fits right into the M10F crosschill. I suggest adding a sensor for water temperature. Mine is attached to the fitting at the radiator inlet. The motherboard BIOS fan controller can use the water temperature to control the radiator fans.
The memory rating on the CPU is just intel's no-risk guarantee. The CPU and board can handle faster speeds than 2666. Let the M10F memory rating be your guide. How much is worth it to you depends on what use you'll make of it. 3200 to 3600 speeds should be easy to do using XMP. Expect higher cost for the higher clocks. For the sort of gaming a 1080ti can do, you could perhaps justify 3600 memory. The Formula isn't the greatest for competitive overclocking, so I don't think any memory 3800 or higher will do you any good at all.
The need for extra PSU capacity with water cooling comes from the temptation to overclock. With stock clocks and XMP memory speed, 750 watts will work well. It depends how you're going to use it. Call it 50 watts for the motherboard, ethernet port, audio, USB, storage, etc. Another 20 watts for pump and fans. Four-core CPU power can easily get over 150 watts when pushed. Add another 350 watts for a pushed water cooled 1080ti and you've filled a 750-watt PSU past its most efficient operating point. For a mildly overclocked gaming rig, I'd suggest a 1000 watt PSU. I use a 1200 watt PSU for serious competitive overclocking. Skimping on the PSU is an easy way to invite mysterious troubles.
The memory rating on the CPU is just intel's no-risk guarantee. The CPU and board can handle faster speeds than 2666. Let the M10F memory rating be your guide. How much is worth it to you depends on what use you'll make of it. 3200 to 3600 speeds should be easy to do using XMP. Expect higher cost for the higher clocks. For the sort of gaming a 1080ti can do, you could perhaps justify 3600 memory. The Formula isn't the greatest for competitive overclocking, so I don't think any memory 3800 or higher will do you any good at all.
The need for extra PSU capacity with water cooling comes from the temptation to overclock. With stock clocks and XMP memory speed, 750 watts will work well. It depends how you're going to use it. Call it 50 watts for the motherboard, ethernet port, audio, USB, storage, etc. Another 20 watts for pump and fans. Four-core CPU power can easily get over 150 watts when pushed. Add another 350 watts for a pushed water cooled 1080ti and you've filled a 750-watt PSU past its most efficient operating point. For a mildly overclocked gaming rig, I'd suggest a 1000 watt PSU. I use a 1200 watt PSU for serious competitive overclocking. Skimping on the PSU is an easy way to invite mysterious troubles.
