The highest contrast ratio of the HP205DJB is 80000000:1. That's over four times the contrast ratio of the most frequently found dynamic contrast ratio of 20000000:1. The best contrast ratio of all small monitors that are a similar age to the HP205DJB is 100000000:1 and the worst is Mega Contrast.
Other flatpanel monitors that have an 80000000:1 dynamic contrast ratio currently available that you might want to look at include the Asus VS207 (£79.32) which has a better Rating.
If the contrast ratio of this PC display is not high enough for you then you might also want to consider the Acer 192HQL (£59.99) (100000000:1 and cheaper) or the Acer 176L (£89.65) (100000000:1 and higher rated).