WIFI Problems on Lenovo Ideapad Flex 5 AMD Ryzen 4000u

My wifi connection on ubuntu is very unstable. Every few minutes I lose the wifi connection or I just get very very low Downloadspeeds (just a few Bytes/s). I dont know what to do. It works just fine on windows (i use dualboot). I tried so far: -turning off powermanagement -use different Kernel -looking for driverupdates (found nothing) Can someone please help me?

My wifi driver: RTL8822CE 802.11ac PCIe Wireless Network Adapter

(I am new on Ubuntu or Linux/GNU in general)

RTL8821ce doesn't have a very good driver support from realtek which results in such unstable WiFi behavior. As far as I know the current driver used in Ubuntu is a DKMS module packed using the source of this repository (I'm not sure about that). But there are some fixes on the README for unstable connections that might help.

to quote it:

Unstable connection - slowdowns or dropouts

The problem may be due to the periodic scanning of access points by the network applet.

This fix worked helpful on Pop! _OS/Ubuntu 20.10 and Fedora 33. Both with GNOME and NetworkManager. #179

Set the BSSID from your network applet. In GNOME this can be done in WiFi Settings > Your profile > Identity > BSSID.

We are going to disable the Connectivity Check option in NetworkManager. This by editing the file in /var/lib/NetworkManager/NetworkManager-intern.conf and adding the following instructions at the end:

[connectivity]
.set.enabled=false

Then, just reboot or restart the NetworkManager unit to fix the problem.