John Carmack has done a bit of research on this, he has a good explication on SuperUser http://superuser.com/a/419167 http://superuser.com/a/419167 Edit: Also

John Carmack has done a bit of research on this, he has a good explication on SuperUser http://superuser.com/a/419167 http://superuser.com/a/419167 Edit: Also on his blog http://www.altdevblogaday.com/2013/02/22/latency-mitigation-strategies/ http://www.altdevblogaday.com/2013/02/22/latency-mitigation-... tl;dr High speed video camera capturing button input and screen in the same frame to measure the complete cycle. Diagnosing why is harder.