The granularity of a slider should not be too coarse. For example, if a slider is assigned only four incremental values but is laid out in a two-inch section of the dialog box, users would have to move half an inch to see a change. Avoid jumpiness like this by scaling the size of the slider.
If users need to know the value controlled by the slider, your dialog box should also display the slider's current value. Update this value whenever the slider is moved. It is recommended you also display an edit box that enables users to enter the value rather than use the slider. If you use an edit box this way, update its value; otherwise, display the value in a text tile. The following figure shows a typical combination of slider and edit box: