Windows 7 throws the whole house off the net!

Hello TechArena,
I have a very confusing problem:
We have a little Wireless LAN at home with a Mac and 2 laptops running XP (Lenovo Thinkpads). Everybody's connected via 802.11n to a TP-Link TL-WR841N router which goes to the network via a PPPoE link over ADSL (with an ECI router. So far so good.

Yesterday I upgraded one of the XP laptops to Windows 7 x64 Ultimate, and suddenly the whole house started getting thrown off the net (that is, the PPPoE link crashes). It seems to be related to high-throughput TCP connections since I've been able to play a few hours of TF2 on this same setup...

I've tried disabling IPv6 and turning off all of the Windows 7 TCP bells and whistles (netsh interface tcp set global...), still no dice - as soon as I try to do something heavy over TCP (for example, download a large file over HTTP), the PPPoE connection breaks.

The router log has this:
167 Aug 9 10:10:17 sent [PADI Host-Uniq(0x0000063f)]
168 Aug 9 10:10:22 sent [PADI Host-Uniq(0x0000063f)]
169 Aug 9 10:10:32 sent [PADI Host-Uniq(0x0000063f)]
170 Aug 9 10:11:03 Timeout waiting for PADO packets
171 Aug 9 10:11:08 sent [PADI Host-Uniq(0x00000664)]
172 Aug 9 10:11:08 rcvd [PADO AC-Name:25-9C065010300083 AC-MAC:00:30:88:01:da:8b]
173 Aug 9 10:11:08 sent [PADR Host-Uniq(0x00000664)]
174 Aug 9 10:11:08 rcvd [PADS sess-id(7485)]
175 Aug 9 10:11:08 sent [LCP Req mru=1480 magic=0xc3822e7c]
176 Aug 9 10:11:08 rcvd [LCP Req mru=1492 auth=pap magic=0x21125c2c]
177 Aug 9 10:11:08 sent [LCP Ack mru=1492 auth=pap magic=0x21125c2c]
178 Aug 9 10:11:08 rcvd [LCP Ack mru=1480 magic=0xc3822e7c]
179 Aug 9 10:11:08 sent [PAP AuthReq user="yossefor@tau" password=(hidden)]
180 Aug 9 10:11:08 sent [LCP code=0xc]
181 Aug 9 10:11:08 rcvd [LCP CodeRej]
182 Aug 9 10:11:09 rcvd [LCP Req auth=pap magic=0xc5e68bbf]
183 Aug 9 10:11:09 LCP down
184 Aug 9 10:11:09 LCP down
185 Aug 9 10:11:09 sent [LCP Req mru=1480 magic=0xde774ef4]
186 Aug 9 10:11:09 sent [LCP Ack auth=pap magic=0xc5e68bbf]
187 Aug 9 10:11:09 rcvd [LCP Nak mru=1500]
188 Aug 9 10:11:09 sent [LCP Req magic=0xde774ef4]
189 Aug 9 10:11:09 rcvd [LCP Ack magic=0xde774ef4]
190 Aug 9 10:11:09 sent [PAP AuthReq user="***" password=(hidden)]
191 Aug 9 10:11:09 sent [LCP code=0xc]
192 Aug 9 10:11:09 rcvd [PAP AuthAck ""]
193 Aug 9 10:11:09 sent [IPCP Req addr=0.0.0.0 dns1=0.0.0.0 dns3=0.0.0.0]
194 Aug 9 10:11:09 rcvd [IPCP Req addr=132.66.8.10]
195 Aug 9 10:11:09 sent [IPCP Ack addr=132.66.8.10]
196 Aug 9 10:11:09 rcvd [IPCP Nak addr=132.66.237.97 dns1=132.66.17.135 dns3=132.66.17.137]
197 Aug 9 10:11:09 sent [IPCP Req addr=132.66.237.97 dns1=132.66.17.135 dns3=132.66.17.137]
198 Aug 9 10:11:09 rcvd [IPCP Ack addr=132.66.237.97 dns1=132.66.17.135 dns3=132.66.17.137]
199 Aug 9 10:11:14 PPPoE connected

Any ideas?

Upgrading from XP laptops to Windows 7 will not support for driver means windows 7 not able to use xp driver else thing you are doing with laptop so there may be chance of mismatch in windows and laptop as some options are made specially for windows xp and can work with win 7 only with proper driver and support and still there is still time to release windows 7 final version ....

Hi I try to look on your practice and I found some data. You mean PPPOE drops connection when the computer is Windows 7? If you disable the Windows 7 computer, does it work? As a check, if you omit the router and set the PPPOE directly, the connection works? You can also upgrade the NIC driver to the Windows 7 and the router's firmware update. I hope this will help you to solve your issue. If you found any additional solution then share with us thank you.