Freshly upgraded, now Kubuntu won't finish booting.

[Silent Observer]

Hmmm. That might be the problem. Because it's an upgrade, I'm using the same user name I had in 14.04, hence (due to having a separate /home partition that was reused) starting in the same ~/ folder and getting the same KDE profile. I recall that being a problem after a KDE upgrade long ago when I was running MEPIS 11. Root user would have the same problem, because I've used that login once or twice since installing Kubuntu. I'll look up the syntax to create a new user from command line and see if that gets a good start; if it does, then I'll have to decide whether to delete the .kde folder, or create a new user -- either way, I'll have to recreate all my screen customizations from scratch, which is a large part of what I was trying to avoid when I switched to a Kubuntu ("upgradable" really means you spend tens of extra hours before doing a clean install, doesn't it?).

Wouldn't it have made sense to have the OS upgrade also upgrade KDE in a "works afterward" manner? Does the Kubuntu team even test actual upgrades of real systems?

[Snowhog]

Does the Kubuntu team even test actual upgrades of real systems?

Of course they do, and I'm sure you do actually understand that.

Every user case is different, and all the unknown variables simply cannot be taken in to account. We are not all 'cut from the same cloth' as it were.

I've seen more than one commentary about "having two identical PCs" that exhibit "different behaviors" even though both are running the same version of Kubuntu. It happens. Troubleshooting is, like it or not, something that users of Linux; any Linux; have to become, if not comfortable with, at least familiar with.

[Silent Observer]

Troubleshooting is, like it or not, something that users of Linux; any Linux; have to become, if not comfortable with, at least familiar with.

And it's not just Linux, of course -- I've spent a whole weekend more than once trying to get a Windows machine (and not one with a bleeding-edge version) running again. At this point, I can confirm that the problem was partially KDE related; command line installing xfce4 let me log in by selecting xfce session at the GUI login dialog, and following that, I was able to log into Plasma as well. Got my screen customized (mostly, a lot of my eye candy and screen toys -- Galilean moons widget, Lunar phase widget, "put your image here" widget, are apparently not yet available for KDE5). Went into driver manager and installed the "recommended" nVidia driver (361), restarted -- and now I can't get into KDE on 16.04. I can use 16.04 with Nouveau, assuming I can get rid of nvidia-361 from the command line or from inside xfce, but my Einstein@Home won't run with that; it requires the nVidia CUDA driver to use GPU computation (it's set to GPU only, with MilkyWay@Home running on my CPU cores).

[Silent Observer]

Okay, I was able to use Synaptic from the pseudo-Xubunutu I got by installing xfce4 to install the nvidia-340 package, which seems to be okay. There's apparently a problem with the combination of nvidia-361 and KDE5 on my system -- KDE is fine with nvidia-340, and xfce works with nvidia-361.

I do note that most of the desktop effects I'm used to before upgrading are no longer offered -- window animations and such -- as well as the above mentioned widgets that haven't yet been brought forward to KDE5. It's a rather boring-looking system compared to the lush feel I got from 14.04 with KDE4. I don't see it as a big improvement, though it's possible I'll find it more reliable (we'll see about that).

[GreyGeek]

...

I do note that most of the desktop effects I'm used to before upgrading are no longer offered -- window animations and such -- as well as the above mentioned widgets that haven't yet been brought forward to KDE5. It's a rather boring-looking system compared to the lush feel I got from 14.04 with KDE4. I don't see it as a big improvement, though it's possible I'll find it more reliable (we'll see about that).

After trying NEON and 16.04 alpha I came to the same conclusion. The lushness AND power of KDE4, and the fact that the next kubuntu LTS was going to be Plasma5 was enough for me to try Mint 17.3 KDE for three months. BUT ... (there's always a "but", isn't there? ) ... Mint didn't have a useful implementation of the second most powerful feature in Kubuntu besides Plasma4: Btrfs. Snapper working with EXT4 wasn't the same. With some reluctance (Mint is a FINE distro!) I came back to Kubuntu and replaced Mint with Xerus.

Lushness can sometimes be an illusion but I've found that with the right wallpaper and themes I can make some dramatic changes! And, I have btrfs!

So, six weeks into Xerus I find the nagging little bugs and other annoyances gradually disappearing with each update. False crashes have disappeared - applications that throw crash reports but haven't really crashed and keep on running. I find Xerus to be really stable. AND FAST! Some of the widgets that KDE4 had are not on Xerus yet, but widget selections are increasing. And, the repository isn't fully populated yet (GUI for Cuneiform? Tesserect doesn't cut it), but it's getting there too.

[Silent Observer]

I agree, it'll get better -- but as it is, this version of Ubuntu reminds me a lot of Windows 8, in that the next point release may, with luck, be what the initial should have been. I'm planning to change the defaults in GRUB so I get into 16.04 by default, since it works well enough to do what I need to do (pending issues I haven't met yet), it just looks like more of a downgrade than an upgrade. Yes, it's faster -- I get to the GUI login about twenty or so seconds sooner from a restart than with 14.04.4, though I wonder how much of that is just the kernel upgrade, which could in theory have been applied to 14.04 just as easily.

I doubt I'll try Mint -- I used Mint briefly before landing on MEPIS back in 2012, but having to install everything from scratch is most of what I was trying to avoid in switching to (K)Ubuntu. And after briefly fiddling with xfce today, I won't be switching to Xubuntu; nor will I go to Unity Ubuntu or Ubuntu Mate; those interfaces look like alternative methods to make a powerful, modern computer feel like something I could have afforded in 2002, at which time I was still using GEOS in the form of NewDeal Ensemble, in a window inside Win95.

Honestly, if GEOS had grown with the capabilities of hardware, I'd still be using it. I've never seen another word processor or object drawing program that has the versatility and ease of use I had with NewDeal Writer and Draw (either of which could do the other's job, the difference was mainly one of optimization).