RX570 Help Please..

[izzygama]

Hey guys,
Hope everyones good!!
So basicalllyyyyyyyy I'm not that great in terms of PC stuff butttt about 10 months ago i built a gaming rig. 

The specs are as follows :

CPU - Ryzen 3 1200
GPU- Radeon™ RX 570 Gaming 8G
Storage - 1 WD 1TB & 1 120GB SSD WD
Motherboard - gigabyte a320m-s2h 
PSU - 500W EVGA 
RAM - 1 X Crucial Ballistix Sport LT Red 8GB DDR4-2666 

Just a budget rig because I'm a student and thats what I was able to buy . So I used to get around 120 fps on high in BF4 and around 100 high on fornite. But all of a sudden I now get 40 on high in BF4 and really bad stutters in fornite and the fps is around 50 on medium/high. I'm like really sad LOL because i spent all my money on this PC and now all of a sudden its not working properly. Also my monitor is a VGA monitor so i use an adapter from the GPU to get the display. Just thought i should mention that. Also i did an benchmark on a website and its saying that my gpu is performing way below expectation. No idea what to do. Not too great with like temperatures and stuff like that so i haven't really touched around with anything because I'm afraid i might like break the PC components. My amd software is all upto date along with my bios version being 42a. 
I did a valley and heaven benchmark and the scores were - valley = 3394 and heaven = 3412. I have no idea if its good or bad. 
Should I change my monitor to a freesync one? Should I return my GPU?

Please guys I would appreciate any suggestions on how to fix this. 

Thanks

[AdamBGames]

1 minute ago, izzygama said:

Hey guys,
Hope everyones good!!
So basicalllyyyyyyyy I'm not that great in terms of PC stuff butttt about 10 months ago i built a gaming rig. 

The specs are as follows :

CPU - Ryzen 3 1200
GPU- Radeon™ RX 570 Gaming 8G
Storage - 1 WD 1TB & 1 120GB SSD WD
Motherboard - gigabyte a320m-s2h 
PSU - 500W EVGA 
RAM - 1 X Crucial Ballistix Sport LT Red 8GB DDR4-2666 

Just a budget rig because I'm a student and thats what I was able to buy . So I used to get around 120 fps on high in BF4 and around 100 high on fornite. But all of a sudden I now get 40 on high in BF4 and really bad stutters in fornite and the fps is around 50 on medium/high. I'm like really sad LOL because i spent all my money on this PC and now all of a sudden its not working properly. Also my monitor is a VGA monitor so i use an adapter from the GPU to get the display. Just thought i should mention that. Also i did an benchmark on a website and its saying that my gpu is performing way below expectation. No idea what to do. Not too great with like temperatures and stuff like that so i haven't really touched around with anything because I'm afraid i might like break the PC components. My amd software is all upto date along with my bios version being 42a. 
I did a valley and heaven benchmark and the scores were - valley = 3394 and heaven = 3412. I have no idea if its good or bad. 
Should I change my monitor to a freesync one? Should I return my GPU?

Please guys I would appreciate any suggestions on how to fix this. 

Thanks

Can you tell us the gpu and cpu temps? This sounds like thermal throttling

[AndrewB121]

You can check temps with something like HardwareMonitor

[TheMountain28]

change your monitor... AMD RX570 with VGA monitor = NO .

[JetSmokifier16]

Could be temperature throttling, or maybe a utility is lowering the speed of your card. Also check to see if all threads are being utilized because I accidentally turned off one of my cores and my cpu ran at 2 instead of 4 and got like less then half performance