The highest contrast ratio of the HW246HBB is 40000000:1. That's over two times the contrast ratio of a 20000000:1 PC display, which is the most common contrast ratio. The contrast ratio of all comparable spec PC monitors that came out around the same time as the HW246HBB ranges from Mega Contrast (worst) to 100000000:1 (best).
We think you might also be interested in some of the other PC monitors that have a 40000000:1 dynamic contrast ratio currently available including because of it's better review score, the Hannspree HE247DPB (£95.50), or the Hanns.G HE247DPB (£92.99).
PC screens with a higher contrast ratio that might also be worth looking at include the VX2452 (£127.97) (50000000:1 and higher rated), or the VX2252 (£86.09) (50000000:1 and higher rated) both from Viewsonic or the AOC E2461FW (£122.19) (50000000:1 and higher rated).