Internet speed drops when torrent active

[dragonator]

When I turn on Utorrent and have more torrents active, but even as few as 3, the overall internet speed drops to a snail's pace (100-300 kbps). My normal speed is 3000kbps. This is even if I don't download anything. Also I can't seed because the upload speed is affected too. I can only seed to local peers, with whom I have a connection speed of around 3MBps. But this is very rare on international torrents. The seccond I close the program the speed is back to normal. This problem appears with Vuse as well (Azureus).

I have tried everything: unchecking UPnP, NAT and DHT, lowering the connections to 40 and half open slots to 5, patching that eventID4226. What else should I try?

[Ultima]

What router are you using? What modem? When you lower the connections to 40, is that globally, or is that per-torrent? Can you try lowering net.max_halfopen to 2?

[dragonator]

I am not using a router or modem. I am connected to the internet through a LAN cable by my cable company, with a phone as well. The protocol used is PPPoE. The global connections are 60 now and per torrent 20. I lowered even more but nothing happened. If I have more than 5 torrents seeding the overall speed plummets.

[Switeck]

Disable in uTorrent:

UPnP, DHT, LPD, and Resolve IPs

Did you lower half open connection max limit in uTorrent to only 2?

...This is for testing, not necessarily permanent settings.