What is it with MSAA?

[Aleksbgbg]

MSAA is such a GPU powerhog .... I have a R9 390, and whilst playing GTA V can have everything on max (with MSAA set to off) at 1920x1080@59Hz with full FPS (VSync).

 

MSAA:

Turn up to 2x, it goes to 50FPS

Turn up to 4x, it goes to 30FPS

16x, it goes to 10FPS.

 

wat?

 

Worst part is, I've had GTA V PC since it came out and only recently realised I had to have everything on medium because I had MSAA at 8x.

 

Currently have it at 2x with slightly lower settings, and I don't need any more either.

[Atmos]

https://www.youtube.com/watch?v=hqi0114mwtY

edit: rofl for some reason my clipboard didn't copy the youtube link the first time.

 

In short, antialiasing means the gpu as to re-render sometimes entire sections of the screen 2 times, 4 times, or 8 times over to get that buttery goodness.

[LokiFire]

Some GPU's handle AA better than others, kinda surprised a 390 can't handle 4xMSAA in GTA V...

 

 

[Benergy]

5 minutes ago, Aleksbgbg said:

MSAA is such a GPU powerhog .... I have a R9 390, and whilst playing GTA V can have everything on max (with MSAA set to off) at 1920x1080@59Hz with full FPS (VSync).

 

MSAA:

Turn up to 2x, it goes to 50FPS

Turn up to 4x, it goes to 30FPS

16x, it goes to 10FPS.

 

wat?

 

Worst part is, I've had GTA V PC since it came out and only recently realised I had to have everything on medium because I had MSAA at 8x.

 

Currently have it at 2x with slightly lower settings, and I don't need any more either.

I believe MSAA is a type of supersampling, so for example, you render 4 times as many pixels as are actually on your screen, then take the average of every set of 4 pixels to determine the colour of 1 pixel on your actual screen.

 

In other words, you are essentially playing at 4 times the resolution of 1080p. 

[Aleksbgbg]

2 minutes ago, Benergy said:

I believe MSAA is a type of supersampling, so for example, you render 4 times as many pixels as are actually on your screen, then take the average of every set of 4 pixels to determine the colour of 1 pixel on your actual screen.

 

In other words, you are essentially playing at 4 times the resolution of 1080p. 

That would do it, damn.

 

Let me go buy a 4k monitor real quick and turn off MSAA instead

[Kamalcranio]

1 minute ago, Benergy said:

I believe MSAA is a type of supersampling, so for example, you render 4 times as many pixels as are actually on your screen, then take the average of every set of 4 pixels to determine the colour of 1 pixel on your actual screen.

 

In other words, you are essentially playing at 4 times the resolution of 1080p. 

It isn't supersampling. It's actually just the elimination of the jagged corners in an image by aproximation of what your eyes should see versus what they DO see.

Peace.

[SteveGrabowski0]

You might try turning your grass settings to Very High from Ultra. That is an enormous performance killer in GTA V. With my mildly overclocked 970, Xeon E3-1231v3, and DDR3-2400 RAM I'm able to run an almost entirely locked 60 fps with everything maxed out in the main settings except reflection MSAA which I turn off, depth of field and motion blur off (neither makes any performance difference, but I hate both effects), grass at Very High instead of Ultra, 2xMSAA on and FXAA off, and then the advanced settings left alone at the default minimum settings except for the streaming when flying, which I have maxed out since it cuts down on texture pop-in when flying and makes almost no performance difference. The lowest it'll drop in normal gameplay is about 57 fps when driving past Mt Chiliad as the sun is setting when there are lots of shadows. Otherwise the only way I can get below 60 fps is to get a car and do donuts in the grass to kick up a bunch of mud and crap, that can get me into the 40s but I don't count that since it's not normal gameplay. You can do stuff like that to tank performance on almost any game out there.

[SteveGrabowski0]

I find 2xMSAA a must on GTA V though, at least at 1080p. If I just run FXAA I see lots of jaggies on NPCs, but 2xMSAA eliminates that for me. I can't tell the difference between 2x, 4x, and 8xMSAA other than performance loss, though I'm only using a 24" 1080p monitor.

[Bhav]

SSAA and MSAA both require memory bandwidth to work.

 

FXAA and SMAA both run off the shaders / cores, and are much more efficient, but cause blurring. 

[Zodiark1593]

MSAA works by antialiasing the edges of polygons (and sometimes supersampling certain textures) instead of supersampling the entire screen. Depending on polygon density, the performance cost begins to close the gap with the brute-force supersample scheme. With heavy vegetation, MSAA cost increases dramatically. 

 

GTA is also probably a bandwidth heavy game as well, further compounding performance issues.

[Aleksbgbg]

On 13/03/2016 at 6:53 PM, SteveGrabowski0 said:

You might try turning your grass settings to Very High from Ultra. That is an enormous performance killer in GTA V. With my mildly overclocked 970, Xeon E3-1231v3, and DDR3-2400 RAM I'm able to run an almost entirely locked 60 fps with everything maxed out in the main settings except reflection MSAA which I turn off, depth of field and motion blur off (neither makes any performance difference, but I hate both effects), grass at Very High instead of Ultra, 2xMSAA on and FXAA off, and then the advanced settings left alone at the default minimum settings except for the streaming when flying, which I have maxed out since it cuts down on texture pop-in when flying and makes almost no performance difference. The lowest it'll drop in normal gameplay is about 57 fps when driving past Mt Chiliad as the sun is setting when there are lots of shadows. Otherwise the only way I can get below 60 fps is to get a car and do donuts in the grass to kick up a bunch of mud and crap, that can get me into the 40s but I don't count that since it's not normal gameplay. You can do stuff like that to tank performance on almost any game out there.

I need to try that. My only difference to you is that my grass is at High (not Very High) and my FXAA is on. Maybe that is killing the FPS for me as I am running at around 55 FPS usually, which still drops to 45 if at lots of grass. Thanks for the info, this is helpful. Same - I can't live without 2xMSAA but more than that is completely useless waste of power.

[branden_lucero]

just another version of anti-aliasing on top of all other AA options that have been available: it either works for you, or doesnt. and personally, i try not to mess with those settings since it puts strain on your fps too much.

[Aleksbgbg]

1 minute ago, branden_lucero said:

just another version of anti-aliasing on top of all other AA options that have been available: it either works for you, or doesnt. and personally, i try not to mess with those settings since it puts strain on your fps too much.

A friend told me that once and I said to him that it is useful in configuring you for you. You, sir, have changed my mind - I will stop messing with those