FSA SL-K Carbon, 39/53 front (could be 34/50, not positive, got it used and haven't counted)
Shimano Ultegra, 12-25 rear
http://allcdale.com/cannondale_specifications.php?Year=2007&Model=CAAD9%20Optimo%201
Honestly, if the derailleur can't handle this cassette, I'll probably throw a mtb derailleur on the back until I'm in shape enough to go back to stock dura ace.
Yah, i meant the normal hills, which aren't anything like that severe
put my new cassette on the caad9. Now I need to adjust the derailleur and potentially get a new chain, and the local hills shouldn't be quite so brutal anymore.