New nVidia Maxwell chips do not support fast CSAA

nVidia quietly drop the support of MSAA 8x anti aliasing as well, as all the faster CSAA modes completely in the new GeForce 750 ti (GM107).

CSAA was introduced back with the G80 chips (GeForce 8800 GTX) and provided faster antialiasing - the CSAA differ from MSAA when for higher quality it does not use more MSAA samples, yet use the CSAA samples witch consume less memory and need therefore less bandwitch. Only buffers for MSAA 8x need 150MB of ram, while CSAA need only about 25MB.

CSAA works just like MSAA for the game engine, however that could be a disadvantage also, since when you cannot enable MSAA, then you can't enable CSAA. However the CSAA advantages is that it is have lower resource hog for the GPU, for the bus and even for the ram capacity.
Also it have zero impact on texture quality, witch does not degrade to worser (like TXAA does), not even to better quality (like SSAA does).

AMD offers the antialiasing almost similar to CSAA on all GCN Radeons and on Radeons with the Cayman core (VLIW-4 GPU).

I verified with our software team and indeed CSAA has been removed from Maxwell GPUs. Any mixed GPU systems that have both a Maxwell and an older NVIDIA GPU (i.e. Kepler) will also not display CSAA modes.


Not sure that this is a good move, but I never used antialiasing (not having a powerfull enought GPU that can run it) yet, so I probably won't be missing it. However maybe other people see it differently?

I should mention it previously, but… the drop of MSAA 8x in favor of MSAA 8xS also means, that the card(s) are not DirectX 11 compatible, as DX 11 require MSAA 8x to work, unless R32G32B32A32 mode is used:

As I did not uses antialiasing yet, I did not see that as any huge problem, however MSAA 8xS is "supersampling" MSAA, witch means that the picture is rendered in 2x higher resolution using MSAA 4x and then scaled down...

This sounds to be slow from just reading it 🙂

It should be mentioned, that exactly these settings of AA (MSAA 2x, MSAA 4x, MSAA 8xS) did supported GeForce chips in 6xxxx and 7xxxx line, while since the GeForce 8xxxx with G80 chip, witch increased the AA settings significantly.

GeForce 8600 GT AA settings: