900 usd gaming build help

Solution
If It's the Cooler Master G550M (Or Better) I wouldn't replace it, It's OK.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-7600K 3.8GHz Quad-Core Processor ($233.49 @ Amazon)
CPU Cooler: CRYORIG H7 49.0 CFM CPU Cooler ($34.88 @ OutletPC)
Motherboard: ASRock Fatal1ty Z270 Gaming K4 ATX LGA1151 Motherboard ($139.99 @ SuperBiiz)
Memory: G.Skill Ripjaws V Series 16GB (2 x 8GB) DDR4-3000 Memory ($92.99 @ Newegg)
Storage: Samsung 850 EVO-Series 250GB 2.5" Solid State Drive ($97.88 @ OutletPC)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($49.55 @ OutletPC)
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The Cooler Master bronze 550w is not the greatest of units. Would suggest replacing it, however it would still work just fine. Light reading for power supplies => http://www.tomshardware.com/forum/id-2547993/psu-tier-list.html

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-7500 3.4GHz Quad-Core Processor ($198.99 @ SuperBiiz)
Motherboard: Gigabyte GA-B250M-DS3H Micro ATX LGA1151 Motherboard ($73.98 @ Newegg)
Memory: Mushkin Blackline 16GB (2 x 8GB) DDR4-2400 Memory ($88.89 @ OutletPC)
Storage: SK hynix SL308 250GB 2.5" Solid State Drive ($72.99 @ SuperBiiz)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($49.55 @ OutletPC)
Video Card: MSI GeForce GTX 1060 6GB 6GB GT OCV1 Video Card ($248.99 @ SuperBiiz)
Case: NZXT H440 (Black/Red) ATX Mid Tower Case (Purchased For $0.00)
Power Supply: SeaSonic G 550W 80+ Gold Certified Semi-Modular ATX Power Supply ($69.99 @ Newegg)
Operating System: Microsoft Windows 10 Home OEM 64-bit ($88.58 @ OutletPC)
Total: $891.96
 

RCFProd

Expert
Ambassador
If It's the Cooler Master G550M (Or Better) I wouldn't replace it, It's OK.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-7600K 3.8GHz Quad-Core Processor ($233.49 @ Amazon)
CPU Cooler: CRYORIG H7 49.0 CFM CPU Cooler ($34.88 @ OutletPC)
Motherboard: ASRock Fatal1ty Z270 Gaming K4 ATX LGA1151 Motherboard ($139.99 @ SuperBiiz)
Memory: G.Skill Ripjaws V Series 16GB (2 x 8GB) DDR4-3000 Memory ($92.99 @ Newegg)
Storage: Samsung 850 EVO-Series 250GB 2.5" Solid State Drive ($97.88 @ OutletPC)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($49.55 @ OutletPC)
Video Card: MSI Radeon RX 480 8GB GAMING X Video Card ($244.99 @ B&H)
Case: NZXT H440 (Matte Black/Red) ATX Mid Tower Case ($0.00)
Power Supply: Cooler Master 550W 80+ Bronze Certified Semi-Modular ATX Power Supply ($0.00)
Total: $893.77
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-01-24 11:56 EST-0500
 
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