OK, that covers the obvious problems (none of which are there). The next step would be:
./cgminer .. options to connect to a pool ... --verbose --text-only --shares 1 > debug.log 2>&1, pastebin it once it complete and wait for someone with more depth to figure out what's going on..
Ghs / Mhs: yes, my mind was playing tricks with me.
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./cgminer -n
1 GPU devices detected
Pastebin of the log:
http://pastebin.com/BDFyPkjk