The highest contrast ratio of the LG 34UC88 is 1000000:1. That's 99% less contrast ratio than the most common dynamic contrast ratio of 100000000:1. Across all medium monitors that have been on the market for a similar time to the 34UC88 the worst contrast ratio is Mega Contrast and the best is 100000000:1.
It may also be worth also looking at one of the other flatpanel monitors that have a 1000000:1 dynamic contrast ratio currently available including because of it's better review score, the LG 34UM88 ($699.00).
If the contrast ratio of this PC screen is too low for you then you might want to consider the LG 34UM94C-P (10000000:1 and cheaper); or the LG 34UC98 ($980.99) (5000000:1 and higher rated).