Soldato
- CPU: So honestly right now the 8700k is the best gaming CPU. However AMD have the refresh for Ryzen/Threadripper on way. It would be worth waiting accordingly. It is likely that longer term if games go how expected to support greater core count then something like a Threadripper would be more ideal but that is only on the hope of games developing how the developers have suggested. There is no way to suggest which will be best and certainly neither would be best in every way compared to one another.
- Motherboard: The motherboard you mention honestly is fine. Any of the brands top end are comparable so go for what you like the look off as there is minimal/no difference with them. However you will need to decide on CPU brand first and thus wait for AMD refresh before being able to suggest best mobo.
- GPU: 1080Ti would be fine unless you hold out for the next Nvidia series. Unfortunatly AMD are not competing at the top end and what they do have is too expensive right now. Don't go multi GPU, not worth the expense.
- Drives: If you are going for ultimate build and just want best then I wouldn't even worry about any mechanical drive now and go for large SSD storage drive or actually 2x1TB in RAID for instance to maximise performance if that is your aim
- PSU: Don't need more than an 800 watt PSU these days. They run so efficiently and a PC power drawer even with high overclocks and similar will never get anything close to this.
- Keyboard: Avoid corsair for keyboard is my honest view. They are fine in quality however the software is a buggy peace of rubbish and never works properly.
- Case is dependent on looks more than anything tbh. The motherboard you are looking at are ATX so case to suit that size. Although personally an MATX board would be better in a top end selection and you could get smaller footprint.