If you are experiencing lag, first thing you need to check is your internet, try to link to internet using ethernet cable instead of Wi-Fi, check if anyone is sharing your internet or if your bit comet is download something in the background, and restart your router/modem to reset the traffic.
If these don't work, then you can try the following steps.
TCP no delay, which is basically an optimization of network traffic that tries to reduce overall packet volume but can cause extra latency in the connection. This should work on Windows 7 or Vista, though the same principle can probably applied to other operating systems as well.
1. From a command prompt (usually in All Programs -> Accessories -> Command Prompt) run “regedit”
2. Browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters\Interfaces
3. Browse the items under interfaces until you find one that has an IPAddress entry matching the network interface you want to affect (typically LAN IP addresses start with 192.168 or 10.0); note that if your IP address is automatically assigned by a DHCP server you may need to look for a matching DhcpIPAddress instead of IPAddress
4. Right-click on the interface and select New > DWORD (32-bit) Value, name it “TcpAckFrequency”
5. Right-click the new TcpAckFrequency value and select Modify, enter “1″ (Hexadecimal radio button should be selected)
6. Right-click on the interface and select New > DWORD (32-bit) Value, name it “TCPNoDelay” (note that TCP is all uppercase this time – that’s intentional)
7. Right-click the new TCPNoDelay value and select Modify, enter “1″ (Hexadecimal radio button should be selected)
8. Verify that both TcpAckFrequency and TCPNoDelay now show up in the adapter’s property list with types REG_DWORD and values 0×00000001
9. Exit regedit and reboot (reboot is necessary for the changes to take effect!)
Play a game and enjoy your new low ping
(You need to have administrator privileges for this method to work)
1. Click on the Start menu.
2. Search for cmd in the search field.
3. Your computer will find the file cmd.exe, just right click on the file and click on “run as administrator”.
4. In the cmd window, type the following – netsh int tcp global autotuninglevel=disabled
5. Hit enter.
6. You will get a message saying OK and it will take effect immediately after that.
If you want to set your computer to default settings again, type netsh int tcp global autotuninglevel=normal in the cmd.exe windows.