Generally, no, unless your nic or router are malfunctioning in some way. a 10/100 nic router will provide the same bandwidth no matter the brand. If you are experiencing packet loss or latency issues, the problem probably exsists in the amount of hops between you, your isp and the destination. Try doing a tracert to the destination (microsofts servers for xboxlive) or whatever else you are trying to connect to through your pc, and ping those servers as well and look at the response time. If the response time is high, >=300 ms, you can try using a proxy server of some sort through your pc, dont know that you would be able to do that with your xbox though, I'm sure someone out there has done it.