850$ Gaming PC

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Here's the best gaming PC you'd be looking at within your budget.
(All prices are in CAD.)

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-6400 2.7GHz Quad-Core Processor ($234.75 @ shopRBC)
Motherboard: Gigabyte GA-H110M-A Micro ATX LGA1151 Motherboard ($59.75 @ Vuugo)
Memory: Crucial 8GB (2 x 4GB) DDR4-2133 Memory ($64.98 @ DirectCanada)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($62.94 @ Vuugo)
Video Card: Gigabyte GeForce GTX 1060 3GB 3GB Windforce OC Video Card ($274.09 @ DirectCanada)
Case: Corsair SPEC-01 ATX Mid Tower Case ($49.99 @ NCIX)
Power Supply:...

Aeacus

Titan
Ambassador
Here's the best gaming PC you'd be looking at within your budget.
(All prices are in CAD.)

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-6400 2.7GHz Quad-Core Processor ($234.75 @ shopRBC)
Motherboard: Gigabyte GA-H110M-A Micro ATX LGA1151 Motherboard ($59.75 @ Vuugo)
Memory: Crucial 8GB (2 x 4GB) DDR4-2133 Memory ($64.98 @ DirectCanada)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($62.94 @ Vuugo)
Video Card: Gigabyte GeForce GTX 1060 3GB 3GB Windforce OC Video Card ($274.09 @ DirectCanada)
Case: Corsair SPEC-01 ATX Mid Tower Case ($49.99 @ NCIX)
Power Supply: SeaSonic S12II 520W 80+ Bronze Certified ATX Power Supply ($74.99 @ Newegg Canada)
Total: $821.49
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-01-15 23:11 EST-0500

Few words.

Put in medium-end CPU from Skylake family with 4 cores to help in gaming.
Picked H110 chipset MoBo due to the budget limitations.
Added 2x 4GB of DDR4 RAM at speeds of 2133 Mhz, so you can run your RAM in dual channel.
For OS and storage, added a common WD Caviar Blue 1TB HDD.
Managed to fit GTX 1060 3GB GPU in. With this, you can play today's games at 1080p with high/ultra settings and 60+ FPS. (Currently, i also have GTX 1060 3GB in my Skylake build but my GPU maker is MSI.)
Picked a good build quality Corsair case with a window and front blue LED fan for eyecandy. Case also has plenty of additional fan mounts.
And lastly, your system's power plant comes directly from the oldest PSU OEM, Seasonic. S12II-520 is good quality PSU with 80+ Bronze efficiency, silent fan and it comes with 5 years of warranty.

I have S12II-520 in my AMD build as well. (Full specs in my sig.) PSU has served me well for the last 3 years and at some point, it even powered my Skylake build before i bought Seasonic PRIME 650 for it.
 
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