Totally agree with Eto and everyone else here.

Speaking as a network engineer (not a hardware engineer) decreasing your ping times a couple of miliseconds is about the absolute best I can see out of a network card and, to be honest, even that's unlikely.

In a game like wow 5-10ms better ping times isn't going to do much for you at all.

Spend the money on memory like Eto says -- it'll help you a ton more than this card will.