For some reason, I have been unable to properly install Nvidia drivers on my laptop on both Kubuntu 18.04 and 18.10. Kubuntu notifies me that I should install proprietary drivers as soon as I boot into it, but going to the driver section of the settings, I have been unable to install any of the Nvidia packages that are shown there, even if I try the option that is marked as recommended. Trying to install it on the first time shows Kubuntu as trying to install the driver, and then the drivers list simply refreshes, showing that the system is on the nouveau driver. Any further attempts to select one of the nvidia drivers and to lick apply simply results in the list refreshing back on nouveau. And, whenever the next reboot after this failed installation attempt happens, Kubuntu doesn't boot properly anymore. It boots, shows the Kubuntu logo, and then it remains black.
I've met the exact same problem on both 18.04 and 18.10. I saw some Reddit comments mentioning that this is a known issue, something on Nvidia's side I think, but I have not been able to find any details, and I'm not sure what to do.
I have an ASUS X550LB laptop, with a Intel Core i7 4500U, and Nvidia GT 740M.