am using 100Mbps (RM189 RYE package), setup as follow:
ASUS AC1200G+ as my router on groundfloor
TPLINK WA850RE as range extender on 1st floor
desktop PC on 2nd floor connected to the range extender via
TPLINK WN821N wifi receiver
3 users in my home, normal web browsing, no heavy youtuber & i'm the sole person who torrents via BitComet at times & game via PS4 which is connected via LAN on groundfloor
my issue is whenever i'm torrenting & gaming, internet speed will slow down greatly, to the point that google mainpage take seconds to load, youtube mainpage take more than 10 seconds to load, and slow browsing speed to other sites as well. this issue is even more obvious when i'm torrenting.
and i've tried torrenting with only 1 file running, not multiple torrent files. and the D/L speed is only around 1000-2000kb/s, not lighting fast speed.
pls any sifu can enlighten me what's going wrong here

Try limit the torrent connection.. Try different number and see.. Try not push more than 200.