It will help prevent clipping if the signal clips while it's being processed by Foobar2000 or the soundcard's drivers, however if the recording itself is clipping the volume control will not help reduce that. Instead of the volume control for the sole purpose of reducing clipping I reccomend ReplayGain, as it automatically adjusts the volume of each track on-the-fly so they're about the same volume and the files themselve aren't changed (except for a few tags added), plus it's a indicator (though an unreliable one) of how badly compressed (dynamically) some albums are, -8 dB and under is where things really start getting bad.
You can enable Replaygain in Foobar under the Playback preferences. ReplayGain has two modes: track and album. In album mode, the "album" gain (or the average gain of all the tracks on the album) is used, so the tracks are just as loud/quiet relative to each other as they would be without ReplayGain, while the track mode uses the individual ReplayGain values for each track, meaning they'll all be about the same volume. To add ReplayGain tags to files, select the files you want to ReplayGain, right click, and select one of the options from the ReplayGain submenu.