good news people!
after a lot of hunting online over the past couple days, i found out that the problem actually has nothing to do with the nforce2 board, its actually an incompatability between my router and a new default in the tcp subsystem of kernel 18.104.22.168. unfortunately the proper way to fix this issue requires a replacement router, or at least replacement router software, but here's the duct tape and bailing-wire fix:
echo 0 > /proc/sys/net/ipv4/tcp_default_win_scale
or add the line:
net.ipv4.tcp_default_win_scale = 0
... there's another variable you can set to turn off tcp window scaling altogether too. i don't understand it all that clearly myself but this seems to be decent explanation:
also, if you google search for: tcp_default_win_scale 22.214.171.124
then you will come up with a bunch of mailing lists and forums with people talking about this.
so the next question... anyone here happen to know how to fix this on an openbsd-based custom firewall?