Please post the output of " lsmod | grep -iE ‘amd|radeon’ ".
[HR][/HR]But, I’ve just now noticed that, the AMD Ryzen 5 2400G requires at least a Linux Kernel version 4.15 – Leap 15.0 has the version 4.12 Linux Kernel …
You could consider moving to Tumbleweed which currently has the version 4.18 Linux Kernel – more than good enough to support the AMD Ryzen 5 2400G CPU …
[HR][/HR]The Leap 15.0 Mesa should be OK – for Leap 15.0 it’s currently at version 18.0 but, once again, Tumbleweed may, possibly, be better for this AMD Ryzen CPU – Tumbleweed currently has Mesa version 18.2 …