CPU Bottleneck

Hello BeamMp forum. I have an issue with my multiplayer. When there are more than 8+ players on the server my CPU will go all the way up to the 100% use and gpu goes all the way down to the 15-30% use. Fps from stable 70-80 goes to laggy15-18. my temperatures are under 80°C and i closed everything in task manager to have a clean background processes and RAM. is there any solution to fix my problem ? by the way my friend have i5 7400 16gb ram and 1050ti and his game with full server is so smooth.

my pc : i5 9400f,GTX1650 gddr5 4GB,16gb ram,game is installed on 256gb ssd,hdd1TB,144hz 1080p monitor

i tried this solutions : reinstalling windows 10 home edition 64bit (licensed version)
updating and reinstalling cpu and gpu drivers
reinstalling game and mp
relocate game from hdd to ssd

PLEASE HELP :(( :sleepy: