OpenGL & Vulkan

[zinx]

Hello.

I am here to discuss 2 problems that I got with using the Vulkan API on both Windows and Linux OS.

First issue:

I have a problem using Vsync with games/softwares that use the Vulkan API.

Software like Dolphin,PPSSPP and RetroArch get constant tearing issues that I dont get with other API's like Directx 11 or 12.

I am using a Dell Inspiron 17 5000 series.

It's using the AMD GPU Radeon 530 and the Intel GPU Intel UHD 620.

The OS is Windows 10 and the CPU is Intel i7-8550U.

The developers of Dolphin believe it's a driver problem and not a software one.

Here is the bug on their issue tracker : https://bugs.dolphin-emu.org/issues/11674.

I tried to force vsync from AMD settings and it didnt work as well.

Second issue:

I cannot use the AMDVLK driver using Ubuntu 19.04 OS.

The driver refuses to work correctly and displays garbled graphics output as a result.

I already opened an issue on the github repo but no one fixed it yet:

https://github.com/GPUOpen-Drivers/AMDVLK/issues/72.

Thanks.

[dorisyan]

Hi zinx‌, Thanks for your report, I will investigate it as soon as possible.

[zinx]

More info on the AMDVLK driver issue.

It seems like it only affects laptops  , PCs that use Intel GPU as their main GPU and PCs that use Hybrid Graphics.

I also remember that the AMDVLK driver was working before a certain version.

Thanks.

[hitbm47]

Hi zinx‌

VSync and Tripple Buffering in the Radeon settings are only for OpenGL applications as far as I know.

VSync in Wolfenstein II The New Colossus works most of the time, but I do remember occurrences when it did not activate and I had to reset it a few times and possibly delete the profile in Radeon settings and scan for the default profile again.

But I have definitely experienced some problems with Vulkan VSync where it would lock Wolfenstein to 50FPS, and if I looked up and back down it would reset to 75FPS which is my screen's refresh rate.

In addition, locking chill min = chill max = 75FPS & Enhanced Sync = true would cause stutters at 75FPS for me in Wolfenstein. Whereas, limiting chill min = chill max = 70FPS, VSync = disabled, Enhanced Sync = disabled, FreeSync = true would work smooth.

Kind regards

Jacques

[zinx]

Thank you for your response.

I don't have access to FreeSync so I cant know if it could have helped me.

At least the RADV Linux driver have V-Sync working correctly for me so it is solvable on Windows as well.

[dorisyan]

OK, I will test it soon.

[zinx]

I found a test program that could be used for testing https://mega.nz/#!3oNREQTT!untcsi3q_InDBebTIszLKuv8LqMzvtMQ6pbIoJpPa3I

It appears a little stuttery when I try it anyway.

[zinx]

Did someone test it here?

I still get Vulkan tearing/stuttery issues.

Someone even reported about this on AMDVLK driver github issue page : https://github.com/GPUOpen-Drivers/AMDVLK/issues/96

Again , v-sync works correctly with the RADV driver.

[hitbm47]

I do think some of the causes, not necessarily this, could be related to clashes within Radeon Settings itself. The reason I say this, is because changing Chill sliders in the new Radeon Overlay in-game sometimes causes the Global Frame Rate Limiter to also change, which in turn affects other games when you launch them. In addition, radeon Chill sometimes get confused with Chill Max and Global FRTC where FPS would sky-rocket to Global FRTC and then jump back to Chill Max, etc.

Kind regards

Jacques