not exactly helpful advice.
his fx 6100 is struggling hard. how much budget do u have? if its fairly low u can go ryzen 3/i3 8100. going for i5 8400 will be very good for the next 5 years though
My advice is as clear as what i wrote which is to change the system insted of trouble shooting
CPU Bottleneck
FX6100 5415 Passmark = Below I5-4460 / i3-6300 / i3-7100
Getting a used I7 / I5 4th / 6th / 7th gen ought to solve the issue easily within affordable means.
4th gen to reuse rams
6th gen if wnat to use DDR4
Graphic Card = R9 290
It is Known PUBG currently is not optimised for AMD Radeons.
Either live with it change it.
its like having a monitor with Freesync while your GPU only has GSync. Which do you value more and what when how is the end goal.
So i am going with the game ( PUBG ) as the priority here.
It is easier to change the system and enjoy the game earlier than to wait for a fix which will still be bottlenecked and has no ETA.