$ uTorrent was very slow for me until recently I applied a few tweaks. Here's what I did.
Note: Some of the settings mentioned below are optimized for 256k connection. If you want to calculate the optimal settings for your connection, check at the end of this tutorial. But I suggest you to read the entire tutorial for guidance on other settings.
First go to Options>Preferences>Network
1. Under `Port used for incomming connections', enter any port number. It is best to use a port number above 10000. I use 45682.
2. Randomize port each time utorrent starts: UNCHECKED. I leave this unchecked because I have a router. If you do not have a router or a firewall, and want extra security,check this option.
3. Enable UPnP port mapping (Windows Xp or later only): UNCHECKED. I leave this unchecked because I have experienced it slowing down speeds. It is not needed if you manually port forward.
4. Add utorrent to Windows Firewall exceptions (Windows XP SP2 or later only): UNCHECKED (do this only if you have windows firewall disabled)
5. Global Maximum upload rate (kb/s): [0: unlimited]: 22 (for 256k connection)
6. Protocol Encryption: ENABLED. I would recommend everyone to enable this. This can help increase speeds with many ISPs.
7. Allow incoming Legacy Connections: CHECKED
1. Global Maximum Number of Connections: 130 (for 256k connection)This number should not be set too low or the number of connections made to your torrents will be limited. Setting it too high may cause too much bandwidth to be used and can cause slowdowns.
2. Maximum Number of connected peers per torrent: 70 (for 256k connection)If you see that the peers connected to a specific torrent are exactly this number, or very close, increase this number to improve speeds.
3. Number of upload slots per torrent: 3 (for 256k connection)This depends on how much you want to upload to other users. Do not set too low or it may affect download speeds.
4. Use additional upload slots if upload speed <90%: CHECKED
5. Maximum number of active torrents: 2 (for 256k connection)
6. Maximum number of active downloads: 1 (for 256k connection)
7. Enable DHT Network: CHECKEDThis is recommended to be checked to improve speeds. More people will be available for sharing if this is checked.
8. Enable DHT for new torrents: CHECKED
9. Enable Peer Exchange: CHECKED
10. Enable scrapping: CHECKED
11. Pre-allocate all files: CHECKED
12. Append .!ut to incomplete files: UNCHECKED
If you use Windows XP SP2, patch tcpip.sys with LvlLord's Event ID 4226 Patcher to get better performance.
DO NOT CHANGE THIS OPTION unless you have Windows XP SP2 and have patched tcpip.sys.
You can also patch tcpip.sys with xp-Antispy
If you have a firewall
* Open up the options/preferences/settings for the firewall - usually your firewall will have an icon to click in the taskbar
* Look for the keywords "allow list" or "programs"
* Add the application you want to give access to the internet
* Make sure to save your settings when you are done
If you have a router
1. Go to start>run>type cmd, press enter>type ipconfig, press enter
2. Remember both your ip address and your default gateway
3. Type in your default gateway into your default browser, a password prompt may come up. The default username and password are admin for my router
4. Under `Applications' fill out one line for each p2p client you use
5. You need to use your ip address, the correct port range and set either tcp or udp
6. You can find and change the ports in the actual p2p client's settings, just make sure they are the same in the router
7. Most p2p apps need both tcp and udp checked, if you are not sure check your p2p client's FAQ
8. Save your settings
Check PortForward.com to forward ports for uTorrent.
Some of the settings I mentioned above are relative to my bandwidth.
How to calculate optimal settings for your connection
In order to apply the following tips you need to know your maximum upload and download speeds. You can test your bandwidth over here.
Maximum upload speed
If you use your Maximum upload speed, there won't be not enough space left for the files you are downloading. So you have to cap your upload speed.
This is how I calculate my optimal upload speed...
upload speed * 80%
Maximum download speed
Setting your maximum download speed to unlimited will hurt your connection. So use this to calculate your optimal setting.
download speed * 90%
Maximum connected peers per torrent
upload speed * 1.3
Maximum upload slots
1 + (upload speed / 6)
Disable Windows Firewall
Windows Firewall hates P2P and so disable it and get yourself a decent firewall like Zone Alarm.
And last optimize your Internet connection with TCP Optimizer.
Know any other tricks to increase uTorrent's download speed? Please share them here.