i guess

ccminer30.exe -a x11 -d gtx760 -o pool:port -O worker.user:password

or

ccminer30.exe -a x11 -d 0 -o pool:port -O worker.user:password

try it.


EDIT:
And look in the ccminer "READ ME" file for extra info , it is located in the program files folder of ccminer.