Integrated Ethernet chips can and do fail I'd try uninstalling and reinstalling the component first in control panel and recheck the settings. These are generally surface mount and some can be a pain to swap out even with the right equiptment. Which chipset is this we most likely have one if needed. A good trick I've figured out on this type of chip as well as others is to draw most of the solder from the component leads with wick, and then run a size E (smaller of the two E's) Guitar string between the leads and the board.. Then just pull or draw the leads... This is a great low heat and low distortion method.. (heat will damage components)..
On my dell insiron 9100, the ethernet port seems to be broken. None of the lights turn on when connecting to lan. Could it be the chip that controls the ethernet port, could it of been fried from static electricity. I know the port is fine, none of the wires are bent. any other criteria much appreciated

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