PC connection - advice appreciated

[astrocan]

Our PC wil not connect to the tinternet either for web access or email.
Laptops which connect wirelessly are fine but the PC is plugged into the router with a cable.
I have checked the 'network connections' in control panel and there are two. One is called 1394 and all indications are that it seems to be functioning OK. I have tried to do a repair on this connection but got an error message along the lines that it was not set up for TCP/IP protocol. I have also tried going back to a resotre point without result.
The other connection is a LAN connection and there is a message saying that a cable is unplugged. I have plugged and unplugged the cable both ends and both ways round but, no dice. I have a recollection that on previous occasions when I have been prostrate at the alter of the back of the PC, the socket where this cable attaches had a flashing LED next to it. At the moment this light is not flashing, is this the problem? What does it mean? What do I need to fix?
Any advice, particularly that intended for a simpleton, would be greatly appreciated.

 

[rusky]

The 1394 connection is firewire. Ignore it!

Can you try the cable on another PC/another cable to try in the problem PC/a different port on the router??

 

[rusky]

If the LED on the LAN port isn't flashing or lit points it towards being a hardware problem.

 

[astrocan]

It looks like the network socket is US.
I am going to acquire and install a network card in a spare slot. The spec for the motherboard says it supports PCI 1.0 but all I can find are PCI 2.0 Does anyone know if this has a fair chance of working or am I wasting my time.
Motherboard is a NF4ST-A9 about five years old.
Cheers.

 

[ian turner]

That's the pci express slots not the pci slots and pci express network cards were a lot less common than normal pci cards last time I checked and you have 3 pci to 2 pci-e 1 slots