I run PD 0.43-4
The TCP server socket implementation in Windows PD should have the option TCP_NOWAIT so that data gets sent immediately when it arrives in the buffer.
This is the case in the Linux version.
Today I write like 15 times per second to the net and the Linux version receives this fast but the Windows version only produces a output approximately 5 times per second.
I'm not an expert on sockets but I suppose this is what differs? Maybe I should add that I run Windows 98 on the client.