To increase speed you need to get into the router and turn off the super g component in the wireless settings. This was a feature designed for their super g wireless cards however have very little use for anything else. Just use the normal 54Mb/s G standard.
Best of Luck with it....it may also pay to check for any new firmware updates for your router and implement it.
i just got a new macbook, 2.16 ghz, 160 gb hdd, and when i connected it to my wireless at home, a linksys super g router, i get download speeds about 1/8th of my other devices on the network, but the upload speeds are the same. Any ideas?

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