Not all external drives are usb, they can be firewire or esata also, becarefull and read the specs first before purchase.
USB 2.0 drives are backward compatible with usb 1.0 so there would be no need to purchase a pci card just use your regular usb ports on your computer,unless of course you need the additional speed of 2.0 but for pictures and music you should be ok it will just take a bit longer to transfer
USB 2.0 drives are backward compatible with usb 1.0 so there would be no need to purchase a pci card just use your regular usb ports on your computer,unless of course you need the additional speed of 2.0 but for pictures and music you should be ok it will just take a bit longer to transfer