Slimbook Executive report 12 - Still no joy
Updated: December 26, 2025
Sometimes, no news is good news. And early news is bad news. The fact I’m writing my 12th report on this laptop so quickly after I’ve published the 11th piece means that there be old and new and colorful problems in the software stack, big and juicy enough to warrant a fresh article. Indeed.
My Slimbook Executive is a wonderful piece of hardware. It’s slick and sexy, it’s got a great keyboard, and it’s fun to use. For a while, it was simply flawless. A true joy to behold and handle. But then, badly executed [sic] updates ruined its spotless record. Firmware "fixes" …
Slimbook Executive report 12 - Still no joy
Updated: December 26, 2025
Sometimes, no news is good news. And early news is bad news. The fact I’m writing my 12th report on this laptop so quickly after I’ve published the 11th piece means that there be old and new and colorful problems in the software stack, big and juicy enough to warrant a fresh article. Indeed.
My Slimbook Executive is a wonderful piece of hardware. It’s slick and sexy, it’s got a great keyboard, and it’s fun to use. For a while, it was simply flawless. A true joy to behold and handle. But then, badly executed [sic] updates ruined its spotless record. Firmware "fixes" that I didn’t ask for and kernel patches that I can’t really filter out of my list of updates brought in an instability that I’m fighting to this day. I won’t bore you with links, you can check my Linux section and peruse the dozen reports about this machine. Today, we shall talk about what happened in the last month, and, good sirs and madams, was it eventful.

VLC no longer plays some of the fanciest formats
I tried to enjoy a couple of movies in the MKV format. For some reason, VLC only output audio, but no video. Weird. Next, I launched the program from the command line, to see what gives. The error came thus:
xcb_xv vout display error: unknown XVideo YUV format 3231564e (NV12)
Browsing around, all of the Internet said I should change the video decoding to VAAPI. Except, VLC for Ubuntu 24.04 (and consequently, Kubuntu) has been compiled without this option. Thus I could not play the files in question. I installed MPV and SMPlayer (a nicer frontend), and this worked fine. But the very fact I had to fight these 2005-era issues in 2025 makes my blood boil. Hint: Not a problem in older releases of Ubuntu.
System freeze on large file copy from NTFS
Another crap issue. I wanted to copy a dozen 1GB+ files from an external disk, formatted with NTFS, onto my internal NVMe. The copy process via the Dolphin resulted in an almost system freeze. Even the Internet lagged as the system struggled with memory pressure. The load went up to 20-30, my free memory disappeared, and once again, we have a regression that makes my blood boil.
The solution is to tweak your memory management parameters, as if you’re some admin working in a data center. I did this for a living, and I absolutely absolutely hate the fact the Linux "home" distros are configured with the same parameters like real servers. Completely unfit for purpose.
echo 16777216 > /proc/sys/vm/dirty_background_bytes echo 67108864 > /proc/sys/vm/dirty_bytes
This helped some, but not enough. I still had to manually run the sync command, and drop buffers and caches not to have my system freeze while copying data. Utterly utterly pointless, stupid and meaningless.
Funnily, I’ve had rsync tasks configured to copy large data sets from NTFS drives into Linux for years and years now. Never had a problem, even on a crappy Asus eeePC, let alone beefier machines. But we can’t have it nice, can we? So this is another problem I have to add to my most glorious upgrade to 24.04. Complete crap. This is such an amateur hour, it’s depressing.
The old random sleep issues and such? Still here.
Ah, my attempt to fix this problem, induced by bad firmware and bad kernels, didn’t work. In the last report, I tried the latest kernel 6.14, but this didn’t help. At all. I wrote how the offending interrupt gpe count is still there, and yes, predictably, the system does its usual arbitrary sleep, wake, sleep, wake nonsense now and then, at completely random times. Makes the system unreliable, and thus unusable for serious, time-sensitive things like say banking or shopping.
In fact, prior to the publication of this article, I’ve had no less than five suspend-wake sequences in just the last week, twice while I was actually playing some games. Yes, you are doing whateve you’re doing, and the machine simply goes to sleep. No warning. And then it takes times for it to wake, you need to fiddle with the lid, hit the power button a few times, a whole circus od sadness and pointlessness.
New kernel, new problems (with VirtualBox)
Ah! As it happens, I wanted to launch a virtual machine, to do some work. This didn’t work. I encountered one problem, then another. The issue is, these errors prevented me from using the virtual machine and doing what I needed to do right then. I was forced to step into the "system administrator" mode once more and debug pointless crap. This is what kills me. I would sort of need to commit to a daily task of checking everything runs, so that when I actually need it, a silly regression or a new bug won’t suddenly manifest.
Now, what happened? Well. First, the program told me that the kernel driver was not installed. I ran the vboxconfig command, and I realized why - missing kernel headers (in 6.14). Now, this is stupid. Because I had kernel headers for 6.8 and build-essential and dkms, so there’s no reason why I shouldn’t have the headers for the new kernel, even though I "upgraded" manually.

From the vboxconfig run:
This system is currently not set up to build kernel modules. Please install the Linux kernel "header" files matching the current kernel for adding new hardware support to the system. The distribution packages containing the headers are probably: linux-headers-generic linux-headers-6.14.0-35-generic This system is currently not set up to build kernel modules. Please install the Linux kernel "header" files matching the current kernel for adding new hardware support to the system. The distribution packages containing the headers are probably: linux-headers-generic linux-headers-6.14.0-35-generic
I installed the missing package(s):
sudo apt install linux-headers-generic linux-headers-6.14.0-35-generic
And now, there was a brand new error:
VT-x is being used by another hypervisor (VERR_VMX_IN_VMX_ROOT_MODE). VirtualBox can’t operate in VMX root mode. Please disable the KVM kernel extension, recompile your kernel and reboot (VERR_VMX_IN_VMX_ROOT_MODE).
This is the same issue I wrote about in 2011 - how to run VirtualBox and KVM side by side. The only issue is, going from kernel 6.8 to 6.14, for whatever pointless zero-QA reason, my system now loads the KVM module on boot, but it did not previously. Amazing. Quick fix:
sudo modprobe -r kvm_intel
And now, VirtualBox runs fine. We shall talk about this in a separate tutorial.
DOSBox performance
Not the best, I’m afraid. I’m going to talk about this in a dedicated guide, but long story short, the performance in ancient DOS games is not as smooth as it could be, or as it was years and years ago when I used ancient single-core machines in mid-2000s. Yup. If you activate the power-saving mode, you can push your CPU into one of the "lower" power states, and then, everything picks up, and you get stellar performance. Amazingly weird and sad. More on this separately.

Small problems
I also encountered a few niggles that shouldn’t be around. I may have mentioned them in the past, but it is worth bringing them up. After all, Plasma in Kubuntu 24.04 is still fully supported, so these issues ought to be ironed out and fixed, I hope. Namely:
- Kate does not remember the last opened file in its recent list. Never.
- The login screen always shows the battery indicator in the bottom right corner as charging, even when you’re running on battery power, and no charger plugged in. Basically, it’s the wrong icon. Like this:

Notice, Kubuntu guest login on top of Kubuntu host, two different battery icons.
It’s getting worse
Now, please read all my Slimbook Executive reports, if you will. Start at the beginning and work your way through the entire set. You will notice that the quality and stability of the software ecosystem is getting worse and worse. Early on, everything was fine. Now, I have printing problems, power management problems, data copy problems, media playback problems, even DOSBox problems. Absolutely ridiculous.
Before you say Fedora, openSUSE or Debian. Please. Take a look at my hardware conundrum report. Every single distro has issues, with every single hardware. I’ve had all sorts of niggles and issues and problems across the entire range of hardware, from Dell to Asus to LG to HP to Lenovo to Slimbook. Debian, Ubuntu, openSUSE, many a distro that wouldn’t even boot. I’m getting recommendations from my readers every week, try X, try Y. Believe it or not, most of these distros won’t even run on my IdeaPad test laptop.
Ubuntu seems to be doing a rather poor job here, right. But it’s also one of the few distros that didn’t merge the buggy xz code back in the day, and it gives you 10 years of free support and patching. And best driver support, despite all of these problems above.
All I can say, I’m happy I bought myself a Macbook. Very sad. Very happy.
Conclusion
My Slimbook Executive is still a good machine. It does many things well. But I cannot rely on its for certain critical things due to its power management problems, its buggy firmware and such. And the range of fun things is getting narrower by the day. Read carefully: regressions. Zero QA. My functionality is becoming less and less. It was big, not it’s less. Kapish. This is stupid and pointless and self-defeating. But sure, let’s develop another 40 distros, add three more stores, work on 22 new "atomic" flavors, and add Wayland, which breaks tons of good stuff on the graphics side. Sure sure, let’s. That will make Linux better still!
The problem has nothing to do with Slimbook as a vendor. If you need a laptop, these guys do a good job. But the software will ruin your experience. It seems the only reasonable modus operandi for Linux is to run it as a virtual machine. No fancy drivers, and a stable host. Like say an old Windows 10, and you run a virtual machine on top of it, for up-to-date and compliant browsing and such. Apparently, adding real hardware into the mix is too much of a challenge.
The last year or so of Linux almost killed my spirit. One, I am trying to promote Linux everywhere I go, so the more it breaks, the more stupid I look. Two, the nerdy dev-focused lack of product-oriented vision is so dejecting. The world is so much bigger than the 0.1% people who want to tinker with dark-themed terminal window like a student with no deadline, but no. Let’s make the entire experience about that - drab, endless tinkering for the sake of tinkering. I would be livid if not for the fact I got myself a Macbook. It costs money, it’s not a trivial decision, but I know I’ll have the peace of mind I need. And that’s priceless.
And so, here we are. What else can I tell you. After 20 years of using Linux, this is the silliest I’ve felt so far. The worst part, no one cares, nor will anyone ever care. The nerds will dismiss this article as a rant from a "grumpy" guy who runs stuff in a "live session" (90% of comments out there), and then they will go back to writing code with no real objective, no artistic finesse, no philosphy. The end.
Cheers.