SVM systems are a cheaper and flexible way to implement the shared memory programming paradigm. Their huge flexibility is due to their software implementation; however, this is also the main responsible of their performance drawbacks with respect to hardware systems. In this paper we compare a pure software HLRC protocol called the HLRC-DU, versus an improved version of the HLRC protocol that uses hardware support to reduce asynchronous communication. Performances of both protocols are compared over a baseline HLRC protocol. Results show that, by on the half of the benchmarks, our protocol performs better than the hardware approach, even more, in some cases our protocol reaches a speedup higher than 22% with respect to the baseline protocol. Keywords—Shared Virtual Memory Systems, Memory Consistency Models, Memory Consistency Protocols, Asyncrhonous Communication.