Increasing the TCP Receive Window?

I read in PC Magazine, Sept. 2000, page 120, an article about increasing download speeds in DSL and cable modems by editting the registry to increase the TCP receive window. He said, for win98, to go to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP, and I would find a setting called DefaultRcvWindow. I went there, but only found Default. Setting the receive window to 32767 is supposed to cause fewer ACKs, so faster downloads. I put 32767 in the data field next to Default, with no change in performance. Is that Default the same thing as DefaultRcvWindow? If not, how do I add it? Any good links to an article that specifically details how to do this?
Thanks