I recently installed Slackware 15 on an older laptop, Dell Inspiron 11 3000 series 2-in-1. Within minutes of starting KDE it freezes. Mouse and keyboard do not respond. I tried disabling compositor but it does not help. There seem to be a lot of posts on the KDE forum about plasma freezing, but no solutions. One poster suggested it was a driver problem for which there is no solution. I have been away from Slackware and Linux for several years now so I am a little rusty. Any help would be appreciated.
Mike.

The first think I would do is switch over to XFCE and one of the window managers (Fluxbox, for example) to verify that the problem is definitely related to KDE and not something more general.

Need a bit more info, are you running Plasma in X11 or in a Wayland session? Does it hard freeze and you have to force a poweroff or just freeze for a few moments? Also try disabling baloo caching to see if that helps
I would also say if possible see what htop shows, maybe Plasma process is misbehaving or hanging? Thats all I got, hopefully it gets you in the right direction.

X11. It's a hard freeze and I have to force it to power down. I will try disabling baloo and I will see what happens if I run fluxbox.

It froze in fluxbox.

How much RAM does this thing have?

Also, what is the video chipset? (The command lspci should provide this information. You might want to run it before startx.)

Operating System: Slackware 15.0
KDE Plasma Version: 5.23.5
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.3
Kernel Version: 5.15.19 (64-bit)
Graphics Platform: X11
Processors: 4 × Intel® Pentium® CPU N3700 @ 1.60GHz
Memory: 3.8 GiB of RAM
Graphics Processor: Mesa DRI Intel® HD Graphics 405

bash-5.1# lspci
00:00.0 Host bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series SoC Transaction Register (rev 21)
00:02.0 VGA compatible controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Integrated Graphics Controller (rev 21)
00:0b.0 Signal processing controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series Power Management Controller (rev 21)
00:13.0 SATA controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series SATA Controller (rev 21)
00:14.0 USB controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series USB xHCI Controller (rev 21)
00:1a.0 Encryption controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series Trusted Execution Engine (rev 21)
00:1b.0 Audio device: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series High Definition Audio Controller (rev 21)
00:1c.0 PCI bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series PCI Express Port #1 (rev 21)
00:1f.0 ISA bridge: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series PCU (rev 21)
00:1f.3 SMBus: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx SMBus Controller (rev 21)
01:00.0 Network controller: Intel Corporation Wireless 3165 (rev 79)

@mscole, I've had had freezes on this laptop as far as the keyboard and mouse are concerned. I have other machines nearby and have been able to ssh into this laptop when it is frozen and those ssh consoles work just fine. (I'm at least able to issue a reboot command versus a hard power off.)

I'm not sure what is doing it on my laptop (hence my lack of complaining here), but in my case it appears to be weakly related to sound processing. I have no hard evidence of that, merely an impression on my part; please treat this as a hint, not a proscription.

That's certainly adequate RAM and Intel graphics usually work and play well with Linux.

Two thoughts:

Have you looked at the log files, particularly /var/log/messages and /var/log/Xorg.0.log? That's a long shot, because, in freezes, sometimes when the freeze happens, nothing makes it to the logs.

Try booting to a Live CD/USB of something and seeing if the freezes still happen.

Today it froze during the KDE splash screen. I left it for a good ten minutes before I forced it to power down.

@OP

To fix those random freezes, please add in the kernel command line of bootloader (and reboot) :
IF you still have freezes, you can try the harder way:
Yeah, it's the CPU, or rather its power management from the Linux kernel - happens myself to have an Intel Celeron N3150 (from the same series as your CPU) which is affected by those random freezes, BUT it's in a mITX motherboard.

Please note that those commands described by me negatively affects the power consumption, then the battery life.

Will be better if you can live with max_cstate set to 2 because this have a lower impact on power consumption.

1 members found this post helpful.

LuckyCyborg, I'm not conversant with elilo. Am I supposed to add intel_idle.max_cstate=2 to a config file?

IF you use elilo, then probably you have a config file with the path /boot/efi/EFI/Slackware/elilo.conf

On this file you should identify the entry for your current boot item, then to add the following line:
IF the append line already exists, you should just append the command. For example:
Better to show me your elilo.conf contents, to be able to say precisely how to make the change.

If one modifies the lilo.conf file, then one must run the command "lilo" to make the change take effect.

I think "elilo" is the same way...

Nope.