Do all computers bought today have gigabit NICs?
no since most hardware manufcatures still use 10/100mbps, because most people dont have gigabytes routers, so its not worth there while to use gigabyte NIC, a lot of well known brands of motherboards like ASUS/EVGA use gigabytes network cards, but store bought machines still use 10/100 rather than the 10/100/1000