I recently got the Mac Pro 2.4GHz Quad Core with 6GB of RAM. While loading web pages seems fine when I try to download files it crawls as if on dial-up. I checked the internet speed on speedtest.net and I get 4Mbps. My iMac (24") which works on the same wifi network gets 20Mbps. Upload speed is the same (about 1Mbps). Do I need to configure my airport properties? please advise. Thanks.