Originally Posted by Edberg
What is micro-stuttering?
It's an issue with the way that CrossFire/SLI drivers handle Alternate Frame Rendering Mode. Basically what happens (if I'm wrong or using terms incorrectly, please correct me) is a game will send the driver Frame A to be rendered. What the driver will do is send Frame A to the first GPU to be rendered and then request the next frame before A is done and send it to the second GPU to be rendered. What happens here is that Frames A&B are essentially rendered and completed at the same time. The problem is now when the game requests Frames C&D, it's going to take longer to update the screen from Frame B to Frame C than it did to update from Frame A to Frame B. The inconsistent rate at which each frame is rendered/drawn is experienced by some people as "microstuttering" because even though you can have a high framerate, the game still appears to stutter. Personally I don't notice it at all except at lower framerates where the game is unplayable anyway.
Maybe this will help the explanation a bit (note that these numbers are made up for illustrative purposes)
Frame A <-10ms-> Frame B <-40ms-> Frame C <-10ms-> Frame D <-40ms-> Frame E and so on.
Originally Posted by MomijiTMO
I find it hard to believe that they have fixed this hardware issue. I think ATI might have minimised it but micro stuttering would be pretty hard to completely fix.
I don't really think they would necessarily need to make any hardware changes. As far as I know, the issue is specifically with the AFR method and not present with other multiGPU rendering methods such as SuperTiling. I think a driver fix isn't out of the question, all they would really have to do is delay the rendering of every other frame. Although I don't think this is an option they will likely take since it will appear to lower the benefit gained from using a multiGPU configuration, especially when you consider that not everyone notices it.Edited by darkcloud89 - 6/7/08 at 7:29pm