Really happy to see som people with the same problem !
In france for now i don't see anybody with this :/
It seems the Mandrake distro work nice with the last asus driver, but i use gentoo and wouldn't change for an issue.
At last there this what is and what some people from www.x86-secret
tell me to try:
Their main idea was around the mtu value, but after some test it appear it don't change anything to the situation :/
The less bad situation is with the kernel included module how compile nice. Before i tryied the 2 last drivers from asus and get an error of "unknown symbol" named "__udivdi3" after a little search i found a tip for this with a modification explained here :
Maybe the same thing that jhaprins expose with the patch.
Anyway until now, no solutions :/
After some tests on p4c800DLX and p4p800DLX how show the same problem i tried to look the network traffic.
One on the computer with 3c940 one other on a computer working fine.
The result is dramaticly simple
3c940 : resolution request > receive resolution response > send a request of connection to google (i take this example how makes problem to everybody) > don't receive the ACK so resend request...
Whereas the other computer show the ACK on my LAN, there is on the 3c940 how never see them and only for some url (like everyall here) and only under linux (we don't really care about the rest)
I wish i was enoughtly clear (as you see my english is really approximative) and thoses infos will be usefull to find a solution.
If i could help, don't hesitate to ask