Screen tearing always occurs no matter the driver or settings

Description

Windows 10 64 Bit OS
Radeon R9 390X card
LG TV with 4096x2160 resolution at 30hz
Beetle PSX HW core
OpenGL mode chosen in Retroarch and Beetle

Expected behavior

The game plays normally at full speed and does not tear.

Actual behavior

Tearing and/or bad performance. The bad peformance goes away when all vsync related options are disabled.

Steps to reproduce the bug

I have tried all relevant AMD driver options such as force vsync, let the application decide, OpenGL triple buffering, and Radeon Enhanced Sync.

I have tried all relevant Retroarch options such as vsync, hard GPU sync with 0 or 3 frames, and sync to exact content framerate.

Version/Commit

• RetroArch: ebe0d89d
• Build date Sep. 19, 2021

If I had to guess I would say it has something to do with the low refresh rate of the monitor but no other games have given me vsync trouble on this system. The problem is solely confined to Retroarch.

edit:

The Problem with low FPS and tearing occurs with the PCSX Rearmed core also. This computer runs this core about 1000 FPS until vsync is turned on.

edit 2:

I think I have found a workaround. Duckstation core with Vulkan backend selected within Duckstation options. First of all, this has no tearing at all with no vsync options in the AMD driver or retroarch even turned on! Secondly, this core allows for 8x internal resolution with the stage 2 AA shader turned on. The Vulkan backend for Beetle HW crashed when 8x was selected because some limits in the card had been exceeded. In fact, Duckstation crashes when I choose higher than 8x and turn the shader on. Finally, Duckstation has more granularity available in choosing the internal resolution. I wanted to mention also that Duckstation had the same problems as others with OpenGL or Direct3D. Obviously, games look really good on a large 4K screen at this internal resoluton and shader setting.

Start by reproducing the issue with the listed Windows 10, Radeon R9 390X, 4096x2160 at 30 Hz, Beetle PSX HW, and OpenGL configuration. Compare the reported vsync, hard GPU sync, exact content framerate, and driver settings, then verify that gameplay no longer tears or suffers bad performance; the later PCSX-ReARMed and DuckStation observations provide additional comparison cases.