For DVD movies the suggested max speed is 4x. I think for CDs it is 24x max. If you have no problems burning, and playback of movie is fine on your systems, some ppl go up to 8x for DVDs (even higher, but that is not recommended). On CDs ive done 48x and 40x, but 24x doesnt take much more time. For DVDs start with 4x and only increase if you are not having problems, and even then, check discs for playback errors if/when you go faster. Oh, and it depends on what your burner and media speed is rated at. Older burners cant go as fast as the newer ones, but can handle the 4x DVD speed fine.
