Pardon the english but I've been away from Iceland for far too long to actually write anything in Icelandic that wouldn't make me look like a total retard.
A few nights ago I bumped into a rather useful thread on http://www.mmo-champion.com - Namely, a so called lagfix, okay, long story short, this is a registry edit that works for Windows XP and Vista (granted you follow the instructions below), and will decrease your latency in World of Warcraft by quite a substantial amount of milliseconds.
Personally, I went from the usual 200-250ms down to a rock solid stable 80ms, a huuuuuge improvement, if I might say so myself.
Well, let's keep it short, please read all of the below and do not continue unless you are absolutely sure you know how to edit your registry.
The below text is quoted from mmo-champion.com - This has been tested by dozens of people that I know personally and has worked wonders for every one of us, none of us have detected any side effects.
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Lag fix - Repost
I hesitated a lot before reposting it, but I didn't have any hate mail saying "omg you broke my computer !" the first time, so I'll assume it's fairly safe. (It's not like you'll be able to send a mail to complain if your computer isn't working anyway, right ?)
A few weeks ago I posted this fix from the ElitistJerks forums and it worked well for most of the people but it's not really safe and it was supposed to be fixed in 2.3.2, however it seems that the Nagle Algorythm fix in the 2.3.2 patch isn't as effective as expected for most of the players, and if you're in desperate need of a lower ping this is still the best way to go.
<><><> Read this first <><><>
1 - It might have side effects, like slowing down your download speed or affecting your performance on other softwares. (In most case, it doesn't change anything, but you've been warned)
2 - If you're not sure about what you're doing, just don't do it. I don't want to be responsible because you crashed your computer in some way because you made a huge error when editing the registry.
2.1 - Seriously, if you don't know what you're doing, don't do it.
3 - If you don't have the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSMQ\ directory, you can download and apply this file to your registry.
4 - Windows Vista users might want to check this post too.
Source - Elitistjerks.com
1 - TcpAckFrequency - NOTE if you are running Windows Vista this setting may not have any effect - a hotfix is needed which i'm tracking down. This works fine under Windows XP
Type "regedit" in windows "run.." dialog to bring up registry menu
Then find:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\
There will be multiple NIC interfaces listed in there, find the one you use to connect to the internet, there will be several interfaces listed (they have long names like {7DBA6DCA-FFE8-4002-A28F-4D2B57AE8383}. Click each one, the right one will have lots of settings in it and you will see your machines IP address listed there somewhere. Right-click in the right hand pane and add a new DWORD value, name it TcpAckFrequency, then right click the entry and click Modify and assign a value of 1.
You can change it back to 2 (default) at a later stage if it affects your other TCP application performance. it tells windows how many TCP packets to wait before sending ACK. if the value is 1, windows will send ACK every time it receives a TCP package.
2 - TCPNoDelay
This one is pretty simple (Discussed here)
Type "regedit" in windows "run.." dialog to bring up registry menu
Then find:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSMQ\Parameters
Right-click in the right hand pane and add a new DWORD value, name it TCPNoDelay, then right click the entry and click Modify and assign a value of 1.
Click Ok and close the registry editor, then reboot your PC.
Once you're done with the technical stuff (it probably won't take more than 1 minute if you're not too bad at it), you can finally get your reward.
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