This is my first Linux install. Kubuntu reached the desktop, but Ethernet and sound didn't work. After I tried changing the panel layout, the desktop started freezing and going black, sometimes right after login.
The machine has an AMD Ryzen 5 7600X3D, Radeon RX 7600 XT and Realtek RTL8125D Ethernet. Is there a sensible way to troubleshoot this, or should I try another distribution?
I'd start by checking hardware support rather than assuming the panel change caused everything. A newer kernel and drivers may help with the Realtek Ethernet controller or other hardware, but that isn't a diagnosis yet. Check the exact Kubuntu release and kernel version before following advice intended for an older installer.
If you're dual booting, disable Fast Startup in Windows and shut Windows down fully before testing Linux again. If the desktop stays up long enough and you have another way to connect, install the available system updates, then reboot and test Ethernet, sound and graphics separately.
Try Fedora KDE from a live USB before installing anything else. Check Ethernet, audio, display behavior and whether the desktop freezes. It may have a different kernel and software stack, so the comparison could tell you something useful even if you decide to keep Kubuntu.
Don't treat a successful live session as a guarantee, though. If you do install another system, back up anything you need first and check the installer carefully so you don't overwrite the wrong drive or partition.
There's also a possible Ethernet negotiation issue to consider. If you can test a different cable or network device, that may help distinguish a connection problem from a missing or unsupported driver. It wouldn't explain the black screen and sound issue by itself, though.
I'd put the panel customization aside for now. A freeze that happens even when opening a terminal suggests there's more to investigate than icon placement. Test the live desktop without changing settings first, then make one change at a time if it stays stable.
It is reasonable to expect basic settings changes not to take down the desktop. You don't need to assume you broke the system just because the freeze appeared while you were experimenting.
If you're choosing an alternative, Fedora KDE keeps the KDE desktop, while Linux Mint is another option if you're open to a different interface. Bazzite is also an option, but its system image is managed differently from a traditional installation, so check whether that suits how you want to install software.
c.418~brassbutton:
What does that different system management mean in practice?
Answers are reviewed before publication.
Rellix.6m:
What if the screen goes black almost immediately after login, before I can run updates?
Ravnek-3u:
Try a live USB to see whether its desktop stays usable. If it does, that gives you a way to test the hardware without relying on the installed desktop.