The highest contrast ratio of the Asus VB178D is 50000000:1. That's over two times the contrast ratio of a 20000000:1 PC screen, which is the most frequently found contrast ratio. The worst contrast ratio of all LCD screens of a similar spec and age to the VB178D is Mega Contrast and the best is 100000000:1.
It may also be worth considering one of the other PC monitors that have a 50000000:1 dynamic contrast ratio currently available including the Asus VB178D-J which is cheaper.
LCD screens with a higher contrast ratio that might be worth looking at include the Asus VX207NE (100000000:1) which is also cheaper.