If you want one as a backup go HERE and download the #1 listing. The reason there is no lisiting for X64 is because the driver is already in the OS. I never have to load mine when loading either Vista x64 or windows 7 X64.  You should be fine just loading the os as a lot of the drivers are already incorporated into it.   
Hi When I put in my service tag in Drivers & Downloads, I could find under VISTA 32 bit a driver available for my network card.  However when I choose VISTA 64 bit , there is nothing available for my system. Does that mean the vista 32 bit will work for the VISTA 64 bit? Mine Dimension 9200/XPS 410 desktop computer. I do not want to try my clean install of VISTA 64 bit attempt without able to connect to the internet. I do not have a spare computer connected to the internet to ask for help form yourselves. Thank you very much for your thoughts and assistance. Snow
Where to find VISTA 64bit Network Card Adaptors for Intel 82566 DC Gigabit 
Network connection?