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Old 12-08-2010, 06:13 PM   #1802
jleslie
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Join Date: Aug 2002

Location: London, UK
Posts: 1,279
I think the sole point here is that the frame rate of the display has no direct relationship to the rate MA3 updates the 3D scene, which is what the slider is setting.

If I have (which I do) a 60Hz monitor I need a screen mode that runs at 60Hz or the monitor won't show the picture properly (actually it will eat other frequencies, but not much less than 60).

If I set MA3 to 30Hz it will update the 3D picture less often than my screen updates, but it will still look fairly reasonable movement-wise. It's actually updating it in the graphics card's memory, it doesn't write directly to the screen. When the graphics card wants a frame to show it will use the most recent one it has so about half of them will be duplicates.

If I set it to 120Hz then about half the frames MA3 draws will never make it to the screen, they will exist in the graphics card's memory though. If I had a 24Hz screen mode then nearly 100 frames would never be seen, but the graphics card would still put 24 frames a second to the screen, it doesn't care if MA3 is making 120 a second, it just won't display most of them.

All the monitor cares about is getting 60 frames a second, it isn't fussed about how often the content updates.

So what you need is to make sure the MA3 screen mode is 24Hz (I'd do this via the display control panel rather than MA3), not the 3D update rate. You don't care about whether MA3 is making 30 or 120 a sec, as you won't see the extra 6-96 frames. (Well, the card will get hotter if you make 120 a sec - that's why the limit is there, to keep the heat down.)

As a bonus if you set "wait for vsync" then it won't make a new frame until the last one is shown, so you will only get 24 MA3 screens drawn a second regardless of the 3D update rate you choose.

John
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