0.9.9.1 around 30% slower with same exact settings as 0.9.8

[[Unknown]]

Hmm, I'm surprised that it caused such a difference on your hardware. What game is it?

Yes, that will disable CLUT (palette) processing of rendered textures, as well as certain complicated blending effects that OpenGL doesn't natively support. Both should be faster using a lower render resolution, but it must be doing something a lot to be slow on your hardware.

Specifically, disabling slower effects will:
* Sometimes cause black flicker in uncommon cases of render target size change.
* Initialize all render targets as blank, rather than using the current render data (causes some rare stencil testing issues.)
* Ignore shared depth buffers (not used by many games, but will break e.g. Jeanne d'Arc.)
* Allow texturing directly from a buffer to itself (not uesd by many games, undefined behavior in OpenGL, usually causes blocky artifacts.)
* Replace absolute-difference blending with max blending (not commonly used, causes weird graphical artifacts and boxes.)
* Skip the use of a shader lookup to apply precise blending (these modes are not commonly used, but it only uses the lookup when needed; may cause some things to be dark or too bright.)
* Skip applying a CLUT (palette) transformation to rendered buffers. This can cause things to be overly dark, bloom to be too bright or missing, and lots of other things.
* Avoid flushing rendering early when a buffer textures from itself (mainly impacts Ridge Racer iirc.)

So, it changes a lot of things. Definitely could impact color overlays or motion blur. Maybe there's a way to improve the performance on the game you're playing, though, with those effects.

-[Unknown]