Question FPS DROPS IN CSGO

Mar 28, 2019
1
0
10
This is my pc information:
Core: Intel i5-4670
GPU: Zotac 1050ti 4gb
Ram: HyperX 8GB
PSU: 500W
Motherboard: Gigabyte H81M-S

With this PC on CSGO: I have set almost everything in csgo as "low" and I get 220 - 240 fps. But suddenly the fps drops to 20-30 and thats a huge amount of lag experienced and it comes back to normal in few seconds. But this happens atleast twice in one round of csgo game (casual/competitive/etc).
This issue is there in Fortnite also. FPS suddenly drops for a few seconds and is back again.
PLEASE HELP ME. I want to enjoy gaming with this graphic card.