Someone I know is having an issue with internet speed when behind a router. Two different PC's net speed slow down considerably when behind a wireless router. If you try a direct connection to the cable modem, speeds are just fine. He tried a different router from the closet I guess and the same thing happens.
ex. speakeasy speed test directly w/ the cable modem results in avg 24mbps/6mbps
speakeasy speed test w/ a router in the loop results in like .2mbps
I know this does not have a lot of details, but I do not have the liberty of being there. Perhaps I can make it there next week, but I wanted to poll a host of ideas from the community. I searched and found a few relative things.
Make sure either router firewall or windows firewall is turned on, not both
Try different channels
Try different physical locations
Get to the PC in question and run a tracert
Revise RWIN settings
Wireless is usually about half the speed of wired even with good wireless reception. You should try to optimise your reception and avoid interference.
1) raise the router above furniture level
2) Experiment with channels (some will work better or worse depending on your environment)
3) If you can detect strong neighbouring wifi, use a channel 5 stops away from strongest.
4) Relocate cordless phone base or video sender etc.
5) Be prepared to move the computer (or at least turn it so your body is not between the router signal and the wireless adapter's antenna.