[Software] semi-random shutdowns only occuring on linux and not on windows.

[IcarusWasted]

Relevant Specs (full list at bottom of post)
OS: Kubuntu 25.10 (dual booted with windows 11)
KDE Plasma Version: 6.4.5
Kernel Version: 6.17.0-22-generic (64-bit)
Graphics Platform: Wayland
CPU: 16 × AMD Ryzen 7 7700X 8-Core Processor
GPU: AMD Ryzen 7 7700X 8-Core Processor
Memory: 32 GiB of RAM (30.2 GiB usable)
Motherboard: MSI B650 Gaming Plus Wifi

Before i say anything else. I want to specify this: None of these shutdowns have occurred on windows. I dual-boot and i can confirm that these shutdowns are purely linux exclusive.

For the last month or so i have been experiencing frequent shutdowns whenever i use my linux computer. Please note that while i will be using the word ‘shutdown’ to describe them. These are more similar to pressing the power button on the PC rather than shutting down through the OS itself.

While there may be shutdowns that fall outside of the following moulds. It usually goes something like this:

• Type 1: Computer remains online for several hours. Shutdowns are random in this state. Usually lasts for a day or two
• Type 2: Shutdowns occur on key press. But only when the computer has not received input for 5-10 minutes while performing a sedentary activity (ie: watching a youtube video, listening to music, remaining idle). This is the longest lasting state by far. Usually lasting anywhere from 1-3 days. Sometimes whenever i power on the computer after one of these the screen is completely blank, and i have to power it on and off again.
• Type 3: Shutdown consistently occur within 1 minute of making it past the GRUB screen. Most of the time this occurs at the boot screen. Though sometimes it can occur within around 20 seconds after booting into the desktop environment. These states only last for roundabout an hour maximum. But they do have the power to get on my nerves the most.

Most of the time these shutdowns are a constant loop of type 2 and type 3. With type 1 occasionally appearing before leading into the loop again.
Sometimes these shutdowns will cause the computer to stop recognising the bluetooth adapter. though this can be easily fixed by power cycling the machine.

Things i have tried to combat this problem:

• Toggling hibernation mode on windows
• Adjusting cable connections between PC parts (may have helped to trigger type 1 shutdowns though i am not sure about this and it may just be coincidence)
• Running BurnInTest (no errors)
• Running Memtest86 (no errors)
• Power cycling the computer
• Changing the CPU power management profile via terminal
• Plugging the other end of the PSU cable into a wall socket instead of a powerboard.
• Switching Distros (Regata OS to kubuntu)
• Disabling C-States
• Updating the BIOS (removed linux from UEFI boot entries)

As seen above i speculate some underlying linux driver is messing with the computer or a UEFI setting is messing with Linux. Based on the posts I’ve seen while researching this may be something CPU-specific. However I am confident that this is not a hardware issue. Not only for the reasons listed above but also because i have a brother with the exact same PC build as mine running windows 11 and he has not reported any random shutdowns thus far. I’m completely stumped here so if anyone could offer any help it would be appreciated immensely.
Here are my full specs:
Operating System: Kubuntu 25.10
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.2
Kernel Version: 6.17.0-22-generic (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 7700X 8-Core Processor
Memory: 32 GiB of RAM (30.2 GiB usable)
Graphics Processor 1: AMD Radeon Graphics
Graphics Processor 2: AMD Ryzen 7 7700X 8-Core Processor
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7E26
System Version: 1.0
Bios Ver: 7E26v1N2
Bios interface Ver: MSI Click Bios 5

boot1.log file (saved as .txt) is attached. Same as output from journalctl -b -1

[die.boer]

try this 1st

sudo nano /etc/default/grub

find the line GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" and change it to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash amd_pstate=disable processor.max_cstate=5 idle=nomwait"
save and exit (ctrl+O - enter - ctrl+X)
update grub

sudo update-grub

reboot

[IcarusWasted]

Unfortunately that did nothing. Thanks for the tip though!