The question is also asked in this topic. But it's archived and doesn't have an answer.

Is it possible to set up the posts sort by date? In my opinion it would be more clear if users see topic posts sort by date because the thread is more logic. Now the default settings are set up by votes.

Is there any option to set this up by default?

There is no way in which to do that when using the up/down voting system. This is the very purpose of that forum type, as per description. 

Thanks for your answer. Is there a way to unuse/switch off the up/down voting system? Or is it automatically linked to the settings when you set up the forum as an question and answer forum?

You can of course change that. You simply edit the forum, and change the forum type

Yes, I'm aware of that. But if I edit the forum type to 'discussion' it's no longer possible to use the 'mark post as the best answer' option right?

If you switch to a discussion type forum, you can choose to 'Enable solved' on the Display settings tab. That wont give you the vote up/down option, but will give you the mark as solved option. Thats actually what we are using on here, for reference

This is great! Very nice