Not an unusual condition, especially as far as computers are concerned
Situation - 2 computers (W7) and a Nexus tablet. One D-link router, Ethernet cabled to one and wifi'ed to the other and the Nexus. Cabled machine constantly dropped out and now won't connect at all (on all 4 ports), other and Nexus happily wifi-ing via same router. Cabled machine picking up unidentified local outlet but won't/can't log onto the Net. W7 machines have 4 and 8 GB RAM.
Anyone care to take a punt at WTF is going on, please? ... An expert's drop-goal explanation would be even more welcome!!
TIA