Are These Parts Good to Go?

Solution
If you are OK with medium-high graphics details in AAA games, go with 3gb. Ultra settings will take up more than 3gb vram.
You can also consider the rx570 4gb if it's cheaper.
changed ram n psu. stock cooler is enough for that non oc i5. considering adding a 250gb ssd like the SK hynix SL308, MX300, 850 EVO

PCPartPicker part list / Price breakdown by merchant

CPU: Intel - Core i5-8400 2.8GHz 6-Core Processor ($199.89 @ B&H)
Motherboard: MSI - Z370 GAMING PLUS ATX LGA1151 Motherboard ($119.98 @ SuperBiiz)
Memory: Team - Vulcan 16GB (2 x 8GB) DDR4-3000 Memory ($139.99 @ Newegg)
Storage: Seagate - Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($59.99 @ Amazon)
Video Card: Asus - GeForce GTX 1060 6GB 6GB Strix OC Video Card
Case: Thermaltake - View 31 TG ATX Mid Tower Case ($69.99 @ Newegg)
Power Supply: SeaSonic - FOCUS Plus Gold 550W 80+ Gold Certified Fully-Modular ATX Power Supply ($54.90 @ Newegg)
Total: $644.74
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-11-26 07:17 EST-0500
 

Optimized ur build :

PCPartPicker part list / Price breakdown by merchant

CPU: AMD - Ryzen 5 1600 3.2GHz 6-Core Processor ($189.89 @ OutletPC)
Motherboard: Gigabyte - GA-AB350-GAMING 3 ATX AM4 Motherboard ($69.99 @ Newegg)
Memory: GeIL - SUPER LUCE RGB SYNC 16GB (2 x 8GB) DDR4-3000 Memory ($142.99 @ Newegg)
Storage: SK hynix - SL308 250GB 2.5" Solid State Drive ($78.99 @ SuperBiiz)
Storage: Seagate - Constellation ES 2TB 3.5" 7200RPM Internal Hard Drive ($54.99 @ Newegg Marketplace)
Video Card: Asus - GeForce GTX 1060 6GB 6GB Dual Video Card ($269.99 @ Newegg)
Case: Corsair - 270R ATX Mid Tower Case ($44.99 @ Newegg)
Power Supply: Corsair - CXM (2015) 450W 80+ Bronze Certified Semi-Modular ATX Power Supply ($19.99 @ Newegg)
Total: $871.82
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-11-26 10:03 EST-0500
 


Yes it is but the one you mentioned is 3gb. Would that be enough? Also,the motherboard,psu and case are just too darn pricey