If you Can StartX Only by the root User but You Can Not StartX by the Normal Users the this Tip Should Solve the Problem.
Solution:
- Configure/Re-Configure the X Server
X -configure
mv /root/xorg.conf /etc/X11
- Make/Re-Make a Proper .xinitrc
mv ~/.xinitrc ~/.xinitrc.back
cp /etc/skel/.xinitrc ~/.xinitrc