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Hello guys.

Some time ago I noticed terrible stuttering in Skyrim, which was easily fixed by setting game to run in windowed mode. At the same time I noticed flickering (very similar to the DX9 one) in Witcher 2 and again the issue was fixed by running game in windowed mode.

Witcher 2 Fullscreen flickering:
http://www.youtube.com/watch?v=yQw4T15z7GI
Check the white polygon flashing on the left.

When I attempted to record this flickering with FRAPS the bug was just gone. I googled I bit...

1. Similar issue is here with us for about 4 years. I found various topics over the web.
2. Its said it not AMD/ATI specific problem but affects various graphics, or its a game specific behavior.
3. People recommended various solutions. To turn Vsync + Triple buffering ON or OFF.

So I made few tests with OCCT. And here are the results. Stuttering issue was reproducible when:

1. Engine was CPU bound - for that purpose the test ran Low resolution 1024x768 or lower.
2. Engine was running in fullscreen. (obviously).
3. It was measured that FPS fluctuation in windowed mode was less than 1 percent. In fullscreen it was 15%.

So I came to conclusion that the issue exists and can be reproduced under certain circumstances. Now for some known workarounds:

a) Enabling/Disabling Vsync
Does not help on this issue. Lower FPS may cause this issue to be more visible or noticeable. At all Vsync did not helped to remove the issue.

b) Frame limiter
This works perfectly. Frame limiter in RadeonPRO fixed stuttering in Skyrim, flickering in Witcher 2
DXtory helped against stuttering in Skyrim, but issue in Witcher 2 was still present.
FRAPS use frame limiter when recording the game.

c) Running game/engine in windowed mode
Obvious, but also works.


According the forums I reviewed regarding this issue its not certain that its Amd/Ati issue or its reproducable on Nvidia cards. However I was unable to reproduce the bug on Nvidia GTX 650ti.

I would like to ask you guys:
1. Whats the root cause of this issue?
I can say its not game engine and its reproducable only in CPU bound apps. What seems strange to me is fact that its visible only in fullscreen.

2. What about Feature request towards AMD - frame limiter feature?
Its certain that it helped in all currently tested scenarios. While implementation into CCC could be matter of few days...