µTorrent, network connectivity totally lost / RealTek

[vsq]

Hi board,

I thought to register here just for this. Now, I have been battling a very weird problem with newly installed Vista 32-bit SP2 and µTorrent v. 2.2 (also tried 2.0.4 with no luck). The problem probably occurs on 64-bit too. I lose network connectivity when using µTorrent.

The setup:

- No firewalls, except for hardware (Buffalo wlan router + tomato), very capable of running a LOT of connections. The problem machine was NOT on wlan, it was on wired network.

- Clean install of Windows Vista. All drivers updated to the newest versions.

- Basically µTorrent was the only installed program.

The problem:

- µTorrent works ok when started with no torrents. I get the green "Network ok" sign. It starts find nodes and all seems well.

- I add a torrent, then wait something like 10 - 20 seconds. Suddenly, all network access gone. All connections (including Remote Desktop) to the machine are disconnected. Then maybe in a couple of seconds the network starts up again.

The Cure :cool:

- Go to your Device Manager, find Network Adapters, then right click on your NIC, choose Properties.

- Go to Advanced, there you will find multiple properties that have "Offload" in their names. DISABLE all of these! (for example, "UDP Checksum Offload"). BOOM. Everything works better!

It seems that at least RealTek has very poor drivers, they do something what they should not do, when a lot of packets are coming through. The whole NIC stops working for a while dropping all connections, or at least slowing everything down very badly!

This is not directly related to µTorrent, but µTorrent seems to trigger this problem as it generates a lot of traffic that the NIC driver does not like.

Now, as a lot of people tend to do, buy cheap, this same problem in one form or another is present in very many systems. My NIC is a RealTek 8169, which is a cheap gigabit adapter. I have tried three different drivers versions with my card, all them exhibit the same problem in one form or another. Some driver versions work a little better than others.