They see more options probably because they have a new Xtreme edition card, yours is not Xtreme edition. You can still overclock with the slider to the left.
Just noticed that your card should be supported as well so not sure why you miss some of the options. However on the Gigabyte page scroll down to the picture of the Xtreme software and it says..
"(*The interface and functionality of the software is subject to each model.)"