You can also use a custom scale to limit how many values are displayed on your slider and which marks/points actually display values over them.
Just go to the Slider object-Presentation tab and select Use Custom Scale option.
You can define how many major Units you want the slider to display and choose other parameters according to the amount of data you want the slider to display.
Generally for a large number of values, I personally prefer setting the number of minor units to 0. And sort them by ascending numberic value.
Hope that helps.