that's what the Linksys tech guy told me over the phone. He was really helpful running throught the product and troubleshooting everything- and this was 10PM Sunday night. A+ on tech support.The install on my main- wired- XP box was an absolute snap. The install to the win2000 laptop went fine until I tried to connect to the internet- it found the router but no internet.When the tech guy told me that I needed to swap out the cards I told him that this was a packaged system and I doubt the vendor would just "swap out" a packeaged card. I'll find out later on today.But- to date- if your running the platforms I mentioned above, you will not get internet access on your laptop with the version 4 card.