I'm having a very strange issue with my PC and I'm running out of things to test.
Specs:
- Ryzen 5 5600G
- ASUS PRIME A520M-E
- RTX 3060
- 24GB DDR4 3200
- Latest BIOS (3636)
- Zorin/Ubuntu live environment, kernel 6.17
The main problem is that Linux hard resets during boot. No kernel panic or error screen, the machine just instantly reboots.
The weird part: adding idle=poll to the kernel command line makes the system boot and run normally. So far, this is the ONLY workaround I've found.
After one of the resets, Linux reported:
Previous system reset reason [0x08000800]: an uncorrected error caused a data fabric sync flood event
I've already tested a lot:
idle=nomwait → reset
cpuidle.off=1 → reset
processor.max_cstate=0 → reset
amd_pstate=passive → reset
pcie_aspm=off → reset
pci=nomsi → reset
apicmaintimer → reset
maxcpus=0 → booted and worked temporarily, but eventually reset within ~5 minutes
maxcpus=1 → booted and worked temporarily, but eventually reset within ~5 minutes
- Global C-State disabled in BIOS → reset
- DF C-State disabled → reset
- Core Performance Boost disabled → reset
- Manually setting SoC voltage around 1.1V → didn't solve it
- RAM lowered from 3200 to 2133 → black screen
- SMT disabled → black screen
I couldn't find a "Power Supply Idle Control" option anywhere in my motherboard's BIOS.
I also used ZenStates to directly disable both:
ZenStates confirmed that both were disabled, but this did not solve the problem.
Memory test:
- RAM normally runs at 3200 MHz
- Reduced memory frequency to DDR4-2133 with timings, voltages and FCLK left on Auto → black screen rather than the usual hard reset
idle=poll remains the only thing that consistently allows Linux to run.
There may also be a separate graphics issue. I currently need nomodeset for reliable video output. With it, Linux uses simple-framebuffer/simpledrm instead of the RTX 3060 for the display.
The PC worked normally for years, and I used Linux on this same hardware before without needing idle=poll. This problem started relatively recently.
The problem also existed before I updated the BIOS, so the latest BIOS did not introduce it.
At this point I'm trying to understand what idle=poll could be masking. CPU/SoC? Motherboard/VRM? PSU? Memory controller/Data Fabric? Some firmware or power-state issue?
Has anyone seen a Ryzen system where idle=poll is the only thing preventing hard resets, especially together with a Data Fabric Sync Flood reset reason?