Question Unstable internet

[Unlinkable]

I just build a new PC spec is as parts below:
Motherboard : MPG X570 Gaming Edge Wifi
Graphic: AMD Radeon RX 5700 XT
Processors: AMD Ryzen 5 3600 6-Core
Software: Window 10

The internet speed is very unstable. I have tried multiple method and determined my pc is the issue as I checked speed on my iPhone and my brother's Desktop it's getting a steady 85mbps.

 

[Lutfij]

Welcome to the forums, newcomer!

What have you tried to resort to a forum post? It's so that we're not suggesting the same things that didn't work for you. You might want to list your full system's specs.

Please include/list your specs like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
OS:

Check and see which BIOS version your motherboard is on currently. You will also need to see which version of Windows 10 you're on.

 

[Unlinkable]

CPU: AMD Ryzen 5 3600 6-Core
Motherboard: MPG X570 Gaming Edge Wifi
Ram: Corsair 8gb x 21
SSD/HDD: Corsair Force LS SSD 100gb, Samsung HD 500gb, Samsung SSD 860 EVO 1TB
GPU: AMD RX 5700 XT
PSU: Corsair RM750
OS: Latest ( Window 10 version 1909 9/9/2020)

BIOS: 1.20

I just realise my BIOS is old would it help to update?