KDE Neon (18.04 LTS) freezes randomly, hard shutdown required

[MatijaK]

I'm not an expert on Linux, so please point to what more info you need.

Thing is, recently I bought and built a new PC configuration, after this error started showing up and my old PC went away (didn't have any probs until this happened, and suddenly, faulty memory modules when I ran memtest).
The problem started sometime around kernel update 4.15.0-8 and 4.15.0-14 (something like that).

Whilst rebuilding PC I left my graphics card (sapphire AMD r9 380) and power supply.
And this problem keeps happening again, so I'm worrying it will affect other components eventually.

My configuration is:
MSI B450 Tomahawk
Kingston 16 GB, HyperX Predator
AMD Ryzen 1700
AMD r9 380

Description: KDE neon User Edition 5.15
Release: 18.04

Kernel (which I updated using UKUU):
Linux neon-home 4.20.17-042017-generic #201903190933 SMP Tue Mar 19 13:36:11 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

When I run journalctl -b -1 (upon restarting/shutdown) it's red on these lines (closest to when the freeze happens)

may 04 21:48:59 home-pc kernel: [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] *ERROR* [CRTC:44:crtc-0] flip_done timed out
may 04 21:49:09 home-pc kernel: [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] *ERROR* [PLANE:42:plane-5] flip_done timed out
may 04 21:49:09 home-pc kernel: [drm:amdgpu_dm_atomic_commit_tail [amdgpu]] *ERROR* amdgpu_dm_commit_planes: acrtc 0, already busy
may 04 21:49:09 home-pc kernel: WARNING: CPU: 6 PID: 1547 at drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:4458 amdgpu_dm_atomic_commit_tail+0xba9/0xe20 [amdgpu]
may 04 21:49:09 home-pc kernel: Modules linked in: ccm pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) arc4 edac_mce_amd kvm_amd kvm irqbypass rt2800usb snd_hda_codec_realtek rt2x00usb snd_hda_codec_generic rt2800lib sn
may 04 21:49:09 home-pc kernel: ahci realtek libahci wmi gpio_amdpt gpio_generic

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1827737

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[MatijaK (mata987)]

Hi, I am running KDE neon and apport is not found.

Can anyone provide assistance?