Need help picking a PC

[Ben2000]

I've been wanting to build a PC for a while and finally have the money, but not sure if I should buy this prebuilt.

This was going to be my build:
https://pcpartpicker.com/list/xdw9Yr
I was planning on downloading windows 10 free or buying a key off of a resale site.

Prebuilt:
Alienware Aurora R5
i7-6700K CPU with water cooling
16GB DDR4 RAM
NVIDIA® GeForce® GTX 1080 with 8GB GDDR5X
1TB Harddrive 

$1250

He said it was about 6 months old and didn't have much use. It has a wifi adapter and comes with windows 10. I plan on getting the same peripherals and would still need to buy an SSD.

Which is the better deal? Which one is worth it? Need feedback soon because he is going out of town for a month.

[Elehat]

it's actually not a bad deal on the prebuilt, the cpu is one gen old but the difference is minor. Lack of ssd is a bummer, and check what the water cooler is and what type of design the 1080 is; both of these could make it a little loud if the water cooler has a shitty pump or the graphics card has a reference design. Also check the psu, which can be a place some prebuilts try to shave money from. Lastly, see if you have any spare dimm slots for future upgrades.

[genexis_x]

AIO in a prebuilt PC usually sucks

Uses founders edition GPU that runs hot and loud

Uses PSU that has unknown quality

PCPartPicker part list / Price breakdown by merchant

CPU: AMD - Ryzen 5 1600 3.2GHz 6-Core Processor  ($218.58 @ OutletPC) 
CPU Cooler: CRYORIG - H7 49.0 CFM CPU Cooler  ($34.89 @ OutletPC) 
Motherboard: ASRock - AB350M Pro4 Micro ATX AM4 Motherboard  ($82.98 @ Newegg) 
Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-3000 Memory  ($115.99 @ Newegg) 
Storage: SK hynix - SL308 250GB 2.5" Solid State Drive  ($87.88 @ OutletPC) 
Storage: Seagate - BarraCuda 1TB 3.5" 7200RPM Internal Hard Drive  ($45.88 @ OutletPC) 
Video Card: EVGA - GeForce GTX 1080 8GB Superclocked Gaming ACX 3.0 Video Card  ($498.99 @ SuperBiiz) 
Case: Rosewill - GRAM ATX Mid Tower Case  ($24.49 @ Amazon) 
Power Supply: SeaSonic - 520W 80+ Bronze Certified Fully-Modular ATX Power Supply  ($56.99 @ SuperBiiz) 
Wireless Network Adapter: Gigabyte - GC-WB867D-I PCI-Express x1 802.11a/b/g/n/ac Wi-Fi Adapter  ($29.99 @ SuperBiiz) 
Total: $1196.66
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-05-27 23:36 EDT-0400
 

PCPartPicker part list / Price breakdown by merchant

CPU: Intel - Core i7-6700K 4.0GHz Quad-Core Processor  ($307.99 @ SuperBiiz) 
CPU Cooler: CRYORIG - H7 49.0 CFM CPU Cooler  ($34.89 @ OutletPC) 
Motherboard: Asus - Z170-K ATX LGA1151 Motherboard  ($95.99 @ Jet) 
Memory: Team - Vulcan 16GB (2 x 8GB) DDR4-2400 Memory  ($94.99 @ Newegg) 
Storage: Seagate - BarraCuda 1TB 3.5" 7200RPM Internal Hard Drive  ($45.88 @ OutletPC) 
Video Card: EVGA - GeForce GTX 1080 8GB Superclocked Gaming ACX 3.0 Video Card  ($498.99 @ SuperBiiz) 
Case: Rosewill - GRAM ATX Mid Tower Case  ($24.49 @ Amazon) 
Power Supply: SeaSonic - 520W 80+ Bronze Certified Fully-Modular ATX Power Supply  ($56.99 @ SuperBiiz) 
Wireless Network Adapter: Gigabyte - GC-WB867D-I PCI-Express x1 802.11a/b/g/n/ac Wi-Fi Adapter  ($29.99 @ SuperBiiz) 
Total: $1190.20
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-05-27 23:37 EDT-0400