The issue is not whether or not the Killer NIC K1 works or not. Our testing shows that it does work, but the performance benefits are rather small and inconsistent. Is that worth replacing your free NIC with one that costs $180? Not by our standards. When you compete with something free, you have to offer a substantial, immediately recognizable benefit. The Killer K1 simply doesn't do that. Our testing shows limited benefits, and our subjective opinion is that games don't really feel smoother, more responsive, or less laggy with it.