Hi David,
Right now the only way to do that would be to modify the theme’s functions.php directly, or to copy the entire graphene_slider() function into a child theme’s functions.php and modify it there. Neither of this method is ideal.
Future version will include an intermediate function, graphene_display_slider(), that handles the conditional statements, so that one only needs to modify that intermediate function instead of the graphene_slider() function to achieve what you want. This allows for future updates to the slider code in the theme’s functions.php and still retain the custom conditional statements in the child theme’s functions.php file.
If you want a quick and dirty way of doing it, assuming you are using version 1.0.9.3 of the theme, you can just open up the header.php file and navigate to line 121, and modify it from this:
<?php if (is_front_page() && !get_option('graphene_slider_disable')) : ?>
to this:
<?php if (!get_option('graphene_slider_disable')) : ?>
This is a quick and dirty method because even though it works, the changes you made won’t be retained the next time you update the theme.