Clear all cache for WP Super Cache adds a menu entry to the admin menu to clear the cache completly.
There is no configuration screen for "WP Super Cache - Clear all cache". This is a ScreenShot of the menu entry that it adds (in Spanish).
This second example shows the menu entry from WP Super Cache we see on some installations to empty the cache of the current page. See: The "Delete Cache" button on the admin menu only deletes the cache for the current page.