Yes, the 2600 is definitely powerful enough to pair with the 1070ti. It is one of the better CPUs in the world. You need faster RAM. Ryzen scales well with faster RAM and 2133mhz will give you performance loss. I would look for 3200mhz. I would also get a x470 board. You will need a first generation Ryzen CPU to update the b350 board to work with the 2600. Also, the x470 has better memory support and memory speed. It will be a lot easier to get the memory running at 3200mhz on a x470 board than a b350. I also upgraded to a better quality PSU.
PCPartPicker part list:
https://pcpartpicker.com/list/78Dw3b
Price breakdown by merchant: https://pcpartpicker.com/list/78Dw3b/by_merchant/
CPU: AMD - Ryzen 5 2600 3.4GHz 6-Core Processor ($189.99 @ Amazon)
Motherboard: MSI - X470 GAMING PRO ATX AM4 Motherboard ($119.99 @ Newegg)
Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-3200 Memory ($158.99 @ Newegg)
Storage: Samsung - 860 Evo 500GB 2.5" Solid State Drive ($119.94 @ Amazon)
Storage: Seagate - Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($57.89 @ OutletPC)
Video Card: EVGA - GeForce GTX 1070 Ti 8GB SC GAMING ACX 3.0 Black Edition Video Card ($469.99 @ Amazon)
Case: Thermaltake - Core P3 SE Snow Edition ATX Mid Tower Case ($123.08)
Power Supply: SeaSonic - FOCUS Gold 650W 80+ Gold Certified Semi-Modular ATX Power Supply ($59.99 @ Newegg)
Total: $1299.86
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-06-20 16:13 EDT-0400