WIFI signal strength upstairs

[xaero1ne]

So here is my situation. I live in a decent sized home, approx 2000 sq ft,
basement, main floor, 2nd floor. my office/computer/gaming room is set up
in the basement. i have an asus rt-ac56u router with my gaming pc hardwired to it. on the main floor i can get a pretty decent wifi signal and speeds but on the 2nd floor (bedrooms) its brutal. so i got a linksys re6500 range extender and placed it on the mainfloor. now my signal on the mainfloor is great but upstairs is still pretty spotty. (spotty as in watching a youtube video on an iphone/ipad is not doable with out constant buffering and major video quality loss) any ideas or suggestions. i am unable to relocate the pc upstairs as much as i would love to do that. i have configure the asus router to put out as much signal strength as possible.
the router and the exteneder are both located in the approximate center of the house as well. i feel like i may need to get a bigger/stronger router but at the same time i would hate to dish out more cash for little/no results.
plus at the same time i feel like my current set up should be power full enough to cover a 2000 sq ft home, its no mansion, and its pretty open concept.

 

[boosted1g]

2000 sqft with 2 stories is doable, 2000 sqft with basement is not going to happen with only 1 router.

You flat out need a wireless access point upstairs.

You can convert any router into a wireless access point.
If you don't need AC speeds up stairs I would get a TP-LINK wdr3600, otherwise I would get the TP-LINK C7 Archer

To connect the AP to router you will need to use one of these three methods:
BEST: Wired Ethernet straight from router to access point
Better: AV600 powerline adapter
Good: Ubiquiti nanostation (a high powered directional antenna purpose built for this type of task) to pickup your wifi signal that then connects via Ethernet into your access point that then rebroadcasts the wifi.

The "good" method when pieced together is basically an enterprise grade wifi repeater with high powered antenna and dual radios.
Your Linksys wifi extender is just the same parts as a laptop wifi system put into a box with little to no additional power and only has 1 radio and thus has to split your bandwidth in half to talk to both the router and the client device.

 

[xaero1ne]

Thanks for that, looks the the AP upstairs is gonna be the best solution. i think i'll bite the bullet and run a Ethernet cable directly. by doing so should i get rid of the entender? or just leave it as is since it is helping on the main floor somewhat.

 

[boosted1g]

Hopefully the second access point will fill in the gaps

I would prefer a second access point over a range extender since range extenders split the bandwidth in half and do not have a reputation for being reliable (although you are at least using it right where you have the repeater between the source and the area that has bad signal instead of putting it in the area that already has no signal). Now granted I need fast inter-network speeds, while if you just need fast internet speeds then wireless AC has plenty of bandwidth to spare to still meet the needs of your internet connection.