Ah, that's what we call DarkBASIC Classic, or DBC. It's the predecessor to DBPro, is based on an earlier version of DirectX, is not a expandable as DBPro, and is not actively maintained any more.
Despite all that, it still has quite a following:
http://forum.thegamecreators.com/?m=forum_read&i=10
There was even a long-awaited game release a few weeks ago (
Soul Hunter) which should answer any questions about DBC's capabilities.
In addition (and you may not have noticed this), but DBC is a part of that 'Dark Game Studio Bonanza' (the second link I gave).