If you are going to get a x370 motherboard, you will need a 1st generation Ryzen CPU to update the bios for the 2700x to work. Plus, there are some features of the 2700x that will only run on the 400 series motherboard. Then the 300 series has RAM compatibility issues, it will save you a lot of pain to just go with the x470 even though it is a little bit more.
Additionally, you dont need a 750 watt PSU for that system, a 650 watt will be more than enough. I would also go with a little higher speed RAM. Ryzen scales very well with high speed RAM. 3200mhz is the sweet spot.
PCPartPicker part list:
https://pcpartpicker.com/list/Bz9x6s
Price breakdown by merchant: https://pcpartpicker.com/list/Bz9x6s/by_merchant/
CPU: AMD - Ryzen 7 2700X 3.7GHz 8-Core Processor ($329.99 @ Amazon)
Motherboard: ASRock - X470 Master SLI/AC ATX AM4 Motherboard ($143.98 @ Newegg)
Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-3200 Memory ($179.89 @ OutletPC)
Storage: Samsung - 850 EVO-Series 250GB 2.5" Solid State Drive ($99.99 @ Samsung)
Storage: Western Digital - Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($43.85 @ OutletPC)
Power Supply: SeaSonic - FOCUS Gold 650W 80+ Gold Certified Semi-Modular ATX Power Supply ($62.89 @ Newegg)
Operating System: Microsoft - Windows 10 Home OEM 64-bit ($89.89 @ OutletPC)
Total: $950.48
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-04-22 20:05 EDT-0400