1.how do i know the optimum number of back buffers to use , should i try looping and just using the maximum amount possible. cause as i see making more surfaces uses up the dead time instead of doing nothing. 2.why does creating too many back buffers generate errs , is it because iam abusing the video memory by creating too many surfaces. 3. is using D3DPRESENT_INTERVAL_DEFAULT , then setting the refresh rate to a certian value (that is supported by driver) , a good way yo control FPS.