Hello Mark - have you had a chance to look at the dmesg2.txt I sent you by PM back on the 11th?
I have tested out the router & the Cat 5 lead & they are both fine yet when my laptop is connected to the router by the Cat 5 lead, the light on the LAN port on the router doesn't come on. So if it is a hardware problem it is with the laptop. Anyway I plugged the Ethernet cable from the router to the laptop & kept an eye on the light for the socket on the back of the router which as I made the connection to the laptop briefly flashed & went out - so I deduce my dear Watson that there is an intermittent hardware fault with the RJ45 socket on my laptop ....... B@#*!ck$
(unless you have any other ideas??)
In the meantime to cheaply upgraded my CPU & RAM so its a bit snappier & more resilient in multi-tasking - but alas I feel I might be flogging a dead horse as the charging jack doesn't allow battery charging (mains only + other issues), the Ethernet port is apparently knackered & I think the hard drive is on borrowed time