Settings options. unchecked will not do anything. If you look at the source from kernel.org you will see that the string for that is to re-size the page during rendering on a fixed site. You have to change the UA or user agent to stop mobile rendering.
Here is instructions.
Open your browser.
In the address bar type in. about:debug
and hit enter. You will not see a page displayed but you will see a small flash in the middle of the screen that says Debug Mode.
Then go into your browser settings. Scroll down to the bottom and you will see new options.
At the very bottom one says "UAstring"
select it
Then set it to desktop mode.
