Change output resolution ATI X1900:
Switching output 2, 3840x1024 to 3072x768, it manages to avoid the little stuttering of the image (also changing the output 1, 1280x1024 to 1024x768).
We use lower resolutions LFG and Phoenix, but the result is not compensated due to the loss of image quality.

We found that removing the output 1, full scren off, is also able to reduce stuttering.

At the end opt for 3840x1024.
LFG resolution of (384x288)
1920x10280 phoenix.

thanks