The list of meetings in the 'Show Upcoming Meetings' part of the dashboard includes meetings for all boards. If you want to view only meetings for one particular board, you can filter out meetings for all other boards. To filter out all unwanted board meetings, click the drop-down list beneath the words 'Choose a board name to show only its meetings' and select the board whose meetings you want to display. All other boards’ meetings will be hidden in the list. 

To display all boards’ meetings again, choose 'All' from the drop-down list.