are the port led lights on?? and do they blink if you put in a cable?? if no check to see if someone pulling a joke on you and turned the ethernet and wifi off in the bios. a lot of ethernet issues can be due to the eth wire clip can be broken and the wire is falling out or not in all the way on a hard wired port. also try reinstalling the mb chipset drivers. if one of them got damaged the pci bus may not run right.