https://www.pcbmaster.com/news/solving-bga-soldering-problems.html

as long as it isn't your daily driver you can always take it apart and work on it at your leisure

it has definitely exceeded its designed-life-expectancy at this point

good luck and have fun!

failing hdd/ssd?

I would almost say "impossible" but I choose "highly unlikely", since the system (as already described in earlier posts) is running smooth and stable with many different programs for many, many hours UNTIL I start a game that uses 3-D-graphics.
Even then, I sometimes am able to play for an hour until the whole system freezes with the last 1 second of sound running in an infinite loop.
Upon rebooting and starting the same game again, it may happen after a few minutes. Same with another game.
But not limited to that, as I have also experienced this system freeze while watching a video or even just listening to music (I haven't experienced the latter two in quite a while though).

I hope it goes well, my laptop just died a few weeks ago after a long and eventful life.

I just booted Win 7 and tried to watch a video. Vlc started and a few seconds later, I found myself staring at the grub boot menu again.
Rebooted and tried to start a 3D-shooter. Same result. Also in a third try with a flight simulator.
In each case the whole system crashed in an instant and the machine rebooted.

I hate to confirm it but it indeed looks like a problem with the integrated graphics chipset.

At least under Devuan, I can still watch videos and play a game with 3-D graphics, knowing that the system might or might not freeze.

So the problem is not related to Devuan or any software.

Thanks for all the input in this thread.

* Except for the manual installation of 2 games that i wanted to try out ...

These were two other games that are very small in size and which I manually installed via aptitude in order to see what they were about.
The "games" during which the freezes occured were 3-D-shooters of which one was configured to be used with Wine and the other one extracted in a folder and run natively under Linux.

That would be the first thing for me to consider, had the two games not been running for well over a year without any problems.

Also, system freezes have occured as well when watching videos with vlc or listening to music with audacious.
What those three scenarios have in common is sound.
But the freezes are rather irregular as I can also listen to music and nothing freezes at all (uptime today is 11+ hours without any incident).
Aside from that, I never had any problems with activities involving other programs.

Will now check playing the games over Win 7 just to confirm that it hopefully is not hardware-related.

Maybe "the proof is in the pudding"?

TL;DR:
Your box runs as well as it always has when there is no game software involved.
That being so, you may want to consider that there must be something going on with the combination [game/hardware].

Could be some game [*.conf] issue, game/hardware incompatiblity or just flaky programming*.
Not unheard of, shit happens all the time.

Best,

A.

* Except for the manual installation of 2 games that i wanted to try out ...

you still could check if on the windows 7 side you have similar problems

Already had the same thought a while ago but never did it so far.
Have used Win 7 only for 4 applications and since I managed to run 3 via WINE and one natively, I haven't used Windows at all for at least 2 years now.
But I will do that over the next few days, starting today.
Will report back on that in a few days.

Meanwhile, without playing a game, my system has been running smooth as always (yesterday 15 hours straight).

on myz fujutsu am practically stuck with w7 (next to linux) since with w10 it would immediatelz crash thanks to a buggy nvidia-card or driver issues; on windows 7 it is quite rock-stable only would shutdown if would tax the nvidia-graphics heavy heavily which i don't , but with win10 it would crash immedtaley.

EDIT: ah sorry, crosspost, the laptop in question is still running devuan 3.0, not devuan 4.0; (thanks to nvidia-driver issues).

Can you narrow down when this started with respect to package upgrades (if any)?

With the hint from "rbit", I searched the logs. As the freezes started occuring sometime by the end of november, I only looked for entries that occured in november (starting november 1st):

Start-Date: 2025-11-01  12:51:04
Requested-By: mt (1074)
Upgrade: xserver-xorg-core:amd64 (2:1.20.11-1+deb11u16, 2:1.20.11-1+deb11u17), python-pip-whl:amd64 (20.3.4-4+deb11u1, 20.3.4>
End-Date: 2025-11-01  12:51:53

Start-Date: 2025-11-04  12:51:18
Requested-By: mt (1074)
Upgrade: gimp-data:amd64 (2.10.22-4+deb11u3, 2.10.22-4+deb11u4), libdcmtk15:amd64 (3.6.5-1+deb11u4, 3.6.5-1+deb11u5), gimp:amd64 (2.10.22-4+deb11u3, 2.10.22-4+deb11u4), libgimp2.0:amd64 (2.10.22-4+deb11u3, 2.10.22-4+deb11u4)
End-Date: 2025-11-04  12:52:00

Start-Date: 2025-11-05  19:27:50
Requested-By: mt (1074)
Upgrade: bind9-host:amd64 (1:9.16.50-1~deb11u3, 1:9.16.50-1~deb11u4), bind9-dnsutils:amd64 (1:9.16.50-1~deb11u3, 1:9.16.50-1~deb11u4), bind9-libs:amd64 (1:9.16.50-1~deb11u3, 1:9.16.50-1~deb11u4)
End-Date: 2025-11-05  19:28:06

Start-Date: 2025-11-05  20:39:39
Requested-By: mt (1074)
Install: vectoroids:amd64 (1.1.0-15+b1)
End-Date: 2025-11-05  20:39:46

Start-Date: 2025-11-05  20:43:09
Requested-By: mt (1074)
Install: torus-trooper-data:amd64 (0.22.dfsg1-12, automatic), libbulletml0v5:amd64 (0.0.6-7, automatic), torus-trooper:amd64 (0.22.dfsg1-12+b1), libgphobos1:amd64 (10.2.1-6, automatic)
End-Date: 2025-11-05  20:43:15

Start-Date: 2025-11-14  18:24:25
Requested-By: mt (1074)
Upgrade: libarchive13:amd64 (3.4.3-2+deb11u2, 3.4.3-2+deb11u3), firefox-esr-l10n-de:amd64 (140.4.0esr-1~deb11u1, 140.5.0esr-1~deb11u1), firefox-esr:amd64 (140.4.0esr-1~deb11u1, 140.5.0esr-1~deb11u1)
End-Date: 2025-11-14  18:25:00

Start-Date: 2025-11-18  17:34:05
Requested-By: mt (1074)
Upgrade: gstreamer1.0-gl:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), thunderbird:amd64 (1:140.4.0esr-1~deb11u1, 1:140.5.0esr-1~deb11u1), libgstreamer-gl1.0-0:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), gstreamer1.0-alsa:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), gir1.2-gst-plugins-base-1.0:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), gstreamer1.0-x:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), gstreamer1.0-plugins-base:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), libgstreamer-plugins-base1.0-0:amd64 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4), libgstreamer-plugins-base1.0-0:i386 (1.18.4-2+deb11u3, 1.18.4-2+deb11u4)
End-Date: 2025-11-18  17:34:56

Start-Date: 2025-11-23  11:53:44
Requested-By: mt (1074)
Upgrade: gir1.2-javascriptcoregtk-4.0:amd64 (2.48.5-1~deb11u1, 2.50.1-1~deb11u1), gir1.2-webkit2-4.0:amd64 (2.48.5-1~deb11u1, 2.50.1-1~deb11u1), libjavascriptcoregtk-4.0-18:amd64 (2.48.5-1~deb11u1, 2.50.1-1~deb11u1), libwebkit2gtk-4.0-37:amd64 (2.48.5-1~deb11u1, 2.50.1-1~deb11u1)
End-Date: 2025-11-23  11:54:06

Start-Date: 2025-11-23  21:44:17
Requested-By: mt (1074)
End-Date: 2025-11-23  21:44:18

Start-Date: 2025-11-23  21:44:45
Requested-By: mt (1074)
Remove: python3-pyparsing:amd64 (2.4.7-1), python3-packaging:amd64 (20.9-2), python3-gpg:amd64 (1.14.0-1+b2), torbrowser-launcher:amd64 (0.3.3-6)
End-Date: 2025-11-23  21:45:05

Start-Date: 2025-11-23  22:34:01
Requested-By: mt (1074)
Install: python3-pyparsing:amd64 (2.4.7-1, automatic), python3-packaging:amd64 (20.9-2, automatic), python3-gpg:amd64 (1.14.0-1+b2, automatic), torbrowser-launcher:amd64 (0.3.3-6)
End-Date: 2025-11-23  22:34:11

Start-Date: 2025-11-29  12:15:19
Requested-By: mt (1074)
Upgrade: cups-filters:amd64 (1.28.7-1+deb11u3, 1.28.7-1+deb11u4), libsnmp-base:amd64 (5.9+dfsg-4+deb11u1, 5.9+dfsg-4+deb11u2), libsnmp40:amd64 (5.9+dfsg-4+deb11u1, 5.9+dfsg-4+deb11u2), libqt5core5a:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), qt5-gtk-platformtheme:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libqt5network5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libfontembed1:amd64 (1.28.7-1+deb11u3, 1.28.7-1+deb11u4), libwbclient0:amd64 (2:4.13.13+dfsg-1~deb11u6, 2:4.13.13+dfsg-1~deb11u7), libssh-gcrypt-4:amd64 (0.9.8-0+deb11u1, 0.9.8-0+deb11u2), libqt5dbus5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libsmbclient:amd64 (2:4.13.13+dfsg-1~deb11u6, 2:4.13.13+dfsg-1~deb11u7), libqt5test5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libqt5widgets5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), cups-filters-core-drivers:amd64 (1.28.7-1+deb11u3, 1.28.7-1+deb11u4), libqt5gui5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libqt5printsupport5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libqt5xml5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libqt5opengl5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libqt5sql5:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), cups-browsed:amd64 (1.28.7-1+deb11u3, 1.28.7-1+deb11u4), libsdl2-2.0-0:amd64 (2.0.14+dfsg2-3+deb11u1, 2.0.14+dfsg2-3+deb11u2), libsdl2-2.0-0:i386 (2.0.14+dfsg2-3+deb11u1, 2.0.14+dfsg2-3+deb11u2), samba-libs:amd64 (2:4.13.13+dfsg-1~deb11u6, 2:4.13.13+dfsg-1~deb11u7), libqt5sql5-sqlite:amd64 (5.15.2+dfsg-9+deb11u1, 5.15.2+dfsg-9+deb11u2), libcupsfilters1:amd64 (1.28.7-1+deb11u3, 1.28.7-1+deb11u4)
End-Date: 2025-11-29  12:17:05

Except for the manual installation of 2 games that i wanted to try out, everything else was installed via "aptitude update" and "aptitude upgrade".

While I cannot completely exclude this possibility, I dare to say that it's neither cpu nor RAM-related, as the system has been running for many hours now without any hitch. But then again, I haven't run any games nor watched any videos or listened to music.

That's another thing that I have done about 3 weeks ago.
In one way it is a good thing that this apparently was not the cause (...hoping that the issue is software-related).

I really DO wish it was the kernel. Because that would be very easy to solve.
But the issues started well before the installation of that kernel (which never showed up on the boot menu anyway).

It's the same kernel that's giving you problems, just manifests differently maybe.

Next, following this line...

check your /var/log/apt/history.log and see if there was anything added/updated around the time the issue started.

If you haven't updated recently and the problems just started out of the blue, then I suspect that's old hardware giving up the ghost slowly.

I have a 2005 lappy, old Athlon chip and 1 gb of ram that i've nursed along for quite a few years, but it started doing something similar and then just got worse until one day it simply would not power up.