Question System can't handle 4k YT videos and movies

Nivz0r

Prominent
May 13, 2020
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Hey guys,
In need of your help.
I built a system as a part of a business.
The system is for watching movies and browsing the Internet (YT and etc').
System specs;
Ryzen 5 1400
B450 aorus m
Samsung 860 ssd
Asus Rx 560 4gb .

Added movies to the PC and trying to watch through VLC media player and there are stutters, video isn't smooth, changed settings on TV and PC. (120hz).
But still not smooth.
Trying to put 4k video on YT PC stuck and GPU on 100% struggling.

Is it possible that this GPU isn't strong enough to run movies and videos ?
What about the CPU?
Should I go with Ryzen 5 5600g or intel 11th gen ?
Or a stronger GPU? Which is it ?