You should use Ramachandran plot for the validation.
As Krishnendu suggested is correct. In SAVES server there is a tool procheck, You can use this. Or
you can use several offline software like VMD, UCSF-Chimera ( http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/ramachandran/ramachandran.html ) to get your validation.