Metroid Prime 3 FPS drops after GPU Upgrade

[Danky-Di]

Hey Guys,

I recently upgraded my GPU (NVidia 1080 Ti --> AMD 6900 XT) and suddenly I am encountering strange fps drops (30-45 fps) in Metroid Prime 3.

These fps drops only occur in some situations, e.g.:

• Charging the Beam
• Switching to Scan Visor
• Some particle effects of certain enemies
• Some environmental objects
  

Strangely, when switching Dolphin from (borderless) fullscreen to window, charging the beam und using the scan visor will not lead to stuttering (but the other situations/effects still do).

I have tried changing several options including Vulkan/D3D 12, some Enhancements-options and Hacks-options.
Hybrid ubershaders with ahead compiling are always used as well as AA (8x SSAA), Anisotropic Filtering (16x) and No Post-Processing

Metroid Prime 3 is the only Wii game I own. F-Zero GX runs fine, so I assume that Gamecube games are not affected at all.

Here are my specs and Dolphin version:

• CPU: AMD Ryzen 5950X
• GPU: AMD RX 6900 XT
• MB: Asus TUF Gaming X570-Plus
• RAM: Patriot Viper Steel 32 GB
• OS: Windows 10 20H2
• Dolphin Version: 5.0-15132
  

Any help is appreciated.
Thank you!

[DJBarry004]

SSAA is usually demanding (even more with Ubershaders). You may want to try with FXAA if possible.

[Danky-Di]

Hi,

you are indeed correct.
After switching to MSAA the slowdowns disappeared!
Anyway, I would not have expected that problems in AA could be limited to individual effects/scenarios.

Thank you!

[dezraj]

Just out of curiosity, what internal resolution are you playing in?

[MayImilae]

So different GPU architectures handle different workloads better than others. Nvidia tends to balance out their cards so they are pretty well rounded. It's boring, but consistent. The radeon 6000 series on the other hand is clever, using the infinity cache to boost its performance way beyond what it would otherwise have been. But that does come with some quirks. The 6900 XT is an absolute BEAST at high frame rates, but if you throw a very large high resolution frame at it, it can be too large for the infinity cache and force it to lean on more on its traditional vram. This will cause performance to suffer a lot. You were probably encountering that exact scenario with high internal resolution and SSAA settings.

[Danky-Di]

(09-16-2021, 03:11 PM)dezraj Wrote: Just out of curiosity, what internal resolution are you playing in?

Mostly 4K, but the issue is also present at 1080p with the exact same behavior: constant 60 fps dropping to ~40 fps in certain situations.