Then a good place to start is your specific hardware and your specific situation, not a random video with some jaggies from 2014.
And note a lot of these things can't be "fixed." We haven't yet achieved perfection in anti-aliasing.
ok chill
i5 6500
2x4gb ram hyperx 3200 (underlock from motherboard to 2133) dual channel
motherboard gigabyte GA-B150-HD3P
SSD corshair FORCELE 500gb
GPU Saphire Pulse rx580 8gb
corsair 650
already try:
1.different monitor
2.different cables
3.different ram
4.different gpu
5.fresh windows 7 pro , windows 10 (original full version)