have you tried the "Recent Messages" module?

Click the "Recent Messages link in the top right corner of your browser window (above the header image).... that'll take you into a sortable listing of posts. Be sure to set the second drop down box from the left to "Newest Topics", and then set the drop down box to the right of it to whatever forum you're wanting to view, then click "Go". That'll give you the result you're desiring.

Let me know if that works for you.