After some more testing I verified this only happens when it tries to power off the monitor. I can confirm that disabling the quick monitor power-off and the power management in the screensaver settings makes the kernel work stable. Again, this feature works OK on linux- image-5.4.0-33-generic
** Description changed: linux-image-5.4.0-33-generic Works OK linux-image-5.4.0-37-generic Freezes when leaving idle for some time. Ubuntu 20.04LTS 64 bits. Fully updated. Hardware: AMD Ryzen 7 1800X 32GB RAM (two sticks: Part number KHX2666C16/16G) Asus PRIME A320M-K - latest BIOS installed AMD Radeon R9 390X 8GB NVMe SSD 512GB (I don't recall the brand) Tried AMDGPU and RADEON drivers for the video card. The issue persists. I was not able to find any logs nor kernel panics on the usual log files. Booting the older kernel makes the machine work perfectly stable as before. Most of the time I come back to a black screen. Other times is partially dimmed, like when entering into power save mode, when the screensaver kicks in to shut down the monitor. - Disabling power management did not fix the issue. I will try disabling - the ability to shut down the monitor. + WORKAROUND: + Disabling the ability to shut down the monitor "fixes" the problem. + + In the xscreensaver settings I disabled quick power-off and also + disabled power management, so it never tries to power off the monitor. + Now the system is stable again. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1883472 Title: linux-image-5.4.0-37-generic freezes on idle. linux- image-5.4.0-33-generic works fine. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed/+bug/1883472/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs