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I have a desktop PC with a 1Gb ethernet card as well as a built-in motherboard 100mb/s ethernet card.

Very recently, internet access using these has stopped working. Initially I thought it was a problem with the Windows 7 Home 32bit edition I have installed but the same problem occurs when the machine is booted into Ubuntu 11.

Local network is still available as I can mount a network share with them. But no internet.

This leads me to believe that there is a problem with the ethernet card and the ethernet on the motherboard. Is there a BIOS-like or other non-volatile storage or settings that could have changed on these.

It is also a coincidence that both have failed at the same time.

On the same machine, in Windows 7, a wireless USB receiver stick can receive internet from my ADSL router's wireless. So internet can work on the installation.

Thoughts about what might have happened to the wired-ethernet card and onboard ethernet?


Further detail (apologies for not giving this earlier):

  • A MacBookPro works with internet OK, it is connected to same bridge as desktop (this is why I thought it is a problem with the desktop card or built-in port rather than my general internet connectivity)
  • Bridges are a 4 port XyZel
  • Modem is Thompson speedtouch 580 ADSL


Spare room:                                    Lounge room:   

                                    +---+      +---+    +-------+
Ubuntu 11/Windows 7 32bit home------+ B |      | B +----+ Modem +-----> DSL line
                                    | r |      | r |    +-------+
MacBookPro -------------------------+ i +------+ i |               +------+
                                    | d |      | d +---------------+ NAS  +
Toshiba NB100 ----------------------+ g |      | g |    +--------+ +------+
                                    | e |      | e +----+ Settop |
                                    +---+      +---+    +--------+


I think there is something perhaps more serious with the desktop - it shutdown on its own accord last night. Not wishing to waste your time but if it is OK but still can't connect then this question is still valid so input is welcome.

share|improve this question
You forgot to describe the problem. What happens when you try to access the Internet? Can you ping by IP address? Does DNS work? – David Schwartz Dec 21 '11 at 1:42
Can you ping your Outward Bound Gateway (ie your Router)? – OG Chuck Low Dec 21 '11 at 3:28
+1 @DavidSchwartz I have updated. – therobyouknow Dec 21 '11 at 10:19
Are these powerline bridges or WiFi bridges? If Wifi, are they in WDS mode? If powerline, where is the WiFi coming from? My bet is that this is a bridging issue. The Wifi option works because it avoids the bridging. – David Schwartz Dec 21 '11 at 15:06
+1 @DavidSchwartz they are standard ordinary ethernet wired links. – therobyouknow Dec 21 '11 at 16:17

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