I made made a build for a friend

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Just looking at the above build, I can make out that it for 1080p 144hz gaming. If that's not the case, fill us up like lutfij said.
The parts that need changing :

Cpu 7700k
Cooler it a poor choice for the hot running i7. Get the Scythe Mugen 5
Ram: there is a trident z rgb for the same price
Psu : not a good one. Get a txm 550
Great monitor.

So something like this :

PCPartPicker part list / Price breakdown by merchant

CPU: Intel - Core i7-7700K 4.2GHz Quad-Core Processor ($323.53 @ OutletPC)
CPU Cooler: Scythe - Mugen 5 51.2 CFM CPU Cooler ($46.88 @ OutletPC)
Motherboard: MSI - Z270 GAMING PRO CARBON ATX LGA1151 Motherboard ($166.88 @ OutletPC)
Memory:...

Lutfij

Titan
Moderator
We don't know your friend's budget, usage scenario and ofc when the system will be built. Essentially all the info that is related in the first post of this thread.

Please post a follow up with the necessary information and I'm sure we can build a refined system. I'm also seeing that you could get away with a Ryzen build provided the usage scenario is right. You also missed out on inlcuding an SSD for that price point.
 
Just looking at the above build, I can make out that it for 1080p 144hz gaming. If that's not the case, fill us up like lutfij said.
The parts that need changing :

Cpu 7700k
Cooler it a poor choice for the hot running i7. Get the Scythe Mugen 5
Ram: there is a trident z rgb for the same price
Psu : not a good one. Get a txm 550
Great monitor.

So something like this :

PCPartPicker part list / Price breakdown by merchant

CPU: Intel - Core i7-7700K 4.2GHz Quad-Core Processor ($323.53 @ OutletPC)
CPU Cooler: Scythe - Mugen 5 51.2 CFM CPU Cooler ($46.88 @ OutletPC)
Motherboard: MSI - Z270 GAMING PRO CARBON ATX LGA1151 Motherboard ($166.88 @ OutletPC)
Memory: G.Skill - Trident Z RGB 16GB (2 x 8GB) DDR4-3000 Memory ($137.99 @ Newegg)
Storage: Crucial - MX300 275GB M.2-2280 Solid State Drive ($97.89 @ OutletPC)
Storage: Seagate - Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($66.89 @ OutletPC)
Video Card: Gigabyte - GeForce GTX 1080 8GB G1 Gaming Video Card ($549.99 @ Amazon)
Case: Deepcool - EARLKASE RGB ATX Mid Tower Case ($69.99 @ SuperBiiz)
Power Supply: Corsair - TXM Gold 550W 80+ Gold Certified Semi-Modular ATX Power Supply ($55.98 @ Newegg)
Operating System: Microsoft - Windows 10 Home OEM 64-bit ($89.89 @ OutletPC)
Monitor: Asus - VG248QE 24.0" 1920x1080 144Hz Monitor ($214.99 @ Best Buy)
Total: $1820.90
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-08-08 02:22 EDT-0400

Consider the newly released Vega 56 @400 bucks for gpu.
 
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