EDIT #2: If the sound is OK, go into the Control panel> Programs & Features and delete anything Conexant there. If nothing, back up Registry and search there. You might have to research other names since Conexant changed hands a few times.
This is what I see when I attempt to uninstall from the Control Panel. I have downloaded and installed all Conexant drivers I can find and I continue to get the same popup notification when I boot up. Maybe I just have to live with it.