I noticed that it became common to see newcomer posts with negative votes, and no comments to explain it. 

Sometimes i even wonder why some good questions get downvoted without reason.

Is there a way to add something like : 

* <strike>first downvote for a newcomer post requier a comment.</strike>

* Adding for a new user post an automatic feedback on a downvote pointing to the help to explain which mistake has been made in the post (maybe a with a popin message option, to be even more accurate)

thanks for reading.  

Some example:

* http://serverfault.com/questions/738566/hot-to-prevent-gitlab-autostart-on-boot#738566
* http://serverfault.com/questions/738572/combine-multiple-sshfs-to-form-one-large-file-system
* http://serverfault.com/questions/738526/ubuntu-postfix-mail-log-missing