I tried XP, and am experiencing packet loss while playing online through my isdn router. I was using win2k and had not had any trouble. I had experienced this same phenomenon when win2k first came out until SR1 which fixed the problem. My pings are still low but while I am playing the response is a bit behind the game and slightly jerky like I am playing through a proxy server or running 2 games of quake2 simultaneously. Does anybody have any ideas. I did read one post about setting the network card to 10 or 100 instead of autodetect and will try that in case the card is constantly switching back and forth for some reason. Thanks.
 
VIA 900 Duron
Netgear isdn router