Well before the recent update, ive only started playing the server and i was told i was extremely fast.. ive pvp'd the "fastest" on the server to find that there is indeed a speed cap as regardless of place/lighting we were going hit for it.
There are too many "opinions" as to what makes you fast on mir.. lets be fair that question will never be legit answered.. ive tryed what people say to make them fast and found it was actually slower.. doing no operating system tweaks i managed to hit the speed cap and same speed as the fastest players out there.
Once you reach that speed cap there is no further to go, and a lot of players are at it... the only issue that i can see at the moment is from the recent update the server in general seems sluggish.
The only way to properly test would be to have at least 6 pc's in the same house on the same connection running a vast array of CPU's, types and speeds of ram, gfx brands and models both standard and overclocked to actually see what parts dont work well and go from there.. and that is never going to happen.. so the age old question still goes unanswered..
These arent old files anymore.. ACPI is a thing of the past with these files.. and from what im seeing the advice given to a lot of people is the complete opposite of what worked for me, so my suggestion is.. mess about with your rig.. try an ATI card if you have Nvidia.. try diff ram, try a new CPU.. try different overclocks.. then move onto operating systems..
All you can really do if it bothers you that much as i can fully backup the fastest players on the server saying they are using no 3rd party applications to gain any advantage as i didnt to match them