- Well Mtu 1473 has been proven to uncap speeds, on ps4 I’ve done 2 sets of {5 round tests for both mtu 1500 and 1473, lower mtu in general is proven to lower latency and if it is not actually lowering latency then I am recieving benefit of about 30-60 more download speeds im here to basically understand how to test for optimal mtu if there’s nothing to really test it then nobody really ...