Hi Brad,
What format is your video? ‘HD’ is a bit of a general term. If you don’t know, select one of your clips and press CMD+9 to open then Item Properties window. If you could post a screenshot of what you see there it’d help. It is possible to render in a lower quality but without knowing what format you’re starting with its hard to advise as to the best method.
One thing you might want to do is the following:
Select your sequence and go to Sequence –> Settings
In the window that opens, select the Render Control tab.
Change Resolution to 33% (or 25 or 50%, depending on the quality you need).

You will find that doing this speeds up your render time. Remember to change it back to 100% for your final master though.
Alex Elkins
Twitter: @postbluetv
http://www.PostBlue.tv
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