I've tried both the win32 and linux servers on the exact same machine (fair test) and played on them from the same machine too. You don't get any more fairer that that in a test.
I found the "slow server" flashing was FAR LESS under linux.
One other thought... How many other processes are running on this machine? Is it using X windows? This could slow things down considerably. I run my linux bawx console only. That's probably why it blew away windoze in this test.
Yeah, that one. Its located in Florida so most people from Canada say their ping sucks there, but it does good with peeps in the S-SE. It doesnt come on line until 5:15 eastern.