Flickering and sudden resolution changes on 20.04/18.04 and old Radeon HD 6570 card

[Shihab Shahriar]

Initially, Ubuntu started with far lower resolution than my monitor. I've tried xrandr --newmode command*, it temporarily helps to get back to my original 1600X900 resolution. But now screen sometimes go back to that lower resolution (and randpomly comes back to normal after some time), and xrandr doesn't help.

Plus, my screen keeps flickering, sometimes quite frequently. Combined with low resolution, it has become almost unbearable at this point. Things work alright with windows 10 (dual boot).

Further details:

    1. Sometimes, but not always, simply going to Display Setting by GUI or typing xrandr in command line fixes it.

    2. I sometimes see "drm:radeon_vga_detect [radeon]] ERROR VGA-1: probed a monitor but no|invalid EDID" while shutting down or in /var/log/syslog. Also quite frequently "ERROR:edid_parser.cc(102)] Too short EDID data: manufacturer id" in the log.

    3. Using read-edid package, I noticed that while on low res, it can't detect EDID on any bus. However if I keep running this command, at some point it successfully reads & parses EDID. Then, if I go to Display Setting, or after some time automatically- the resolution comes back to normal.

    4. Reinstalled ubuntu 20.04, removed that cron job. Didn't change the situation.

    5. I've tried Wayland, awesome window manager, lightdm display manager. I'd rather not change the GNOME environment.

    6. Tried Ubuntu 18.04.4 (current OS), now its always low resolution.

Config: CPU: Ryzen 3700x, MB: Asus Tuf x570 Gaming plus, Monitor: Samsung SyncMaster E2020

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xorg 1:7.7+19ubuntu7.1
Uname: Linux 5.7.1-050701-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.15
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Fri Jul 3 20:53:51 2020
DistUpgraded: Fresh install
DistroCodename: bionic
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Advanced Micro Devices, Inc. [AMD/ATI] Turks PRO [Radeon HD 6570/7570/8550] [1002:6759] (prog-if 00 [VGA controller])
   Subsystem: PC Partner Limited / Sapphire Technology Turks PRO [Radeon HD 6570/7570/8550] [174b:e193]
InstallationDate: Installed on 2020-07-02 (0 days ago)
InstallationMedia: Ubuntu 18.04.4 LTS "Bionic Beaver" - Release amd64 (20200203.1)
MachineType: System manufacturer System Product Name
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.7.1-050701-generic root=UUID=e26c767f-e791-4209-905a-0e9eaa3bc363 ro quiet splash vt.handoff=1
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/19/2019
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1405
dmi.board.asset.tag: Default string
dmi.board.name: TUF GAMING X570-PLUS (WI-FI)
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1405:bd11/19/2019:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnTUFGAMINGX570-PLUS(WI-FI):rvrRevX.0x:cvnDefaultstring:ct3:cvrDefaultstring:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.sku: SKU
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.101-2~18.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 19.2.8-0ubuntu0~18.04.3
version.libgl1-mesa-glx: libgl1-mesa-glx 19.2.8-0ubuntu0~18.04.3
version.xserver-xorg-core: xserver-xorg-core N/A
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A
version.xserver-xorg-video-intel: xserver-xorg-video-intel N/A
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A

[Shihab Shahriar (shiahab-shahriar)]

Just wanted to add that after someone suggested the problem might be in GNOME, I've made a fresh installation of Kubuntu 20.04 and haven't had any problem for 2 days.