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It happened again.

Recently my onboard NIC was shorted by a power surge.

I duly installed one of my numerous PCI LAN cards.

For a time, it worked in Ubuntu but not in Win7.

I decided to reinstall all my OSs.

Networking failed across the whole PC.

In Linux, it would only connect if I manually assigned IPs, and even then it wouldn't ping or load any pages.

In Win7, it would declare it had no driver for a generic network card, and when I tried another one it would connect, even ping to domain names, but it would never load pages past the the title, and even then only once.

I also tried accessing the router settings page: same result.

I tried a total of 3 LAN cards, all of which failed drastically. I even tried them in different PCI sockets to no avail.

As before, I know it's not to do with network infrastructure because I can access just fine from a machine that branches from the same point.

I also know it's not an OS problem, as both Win7 and Linux are newly installed and experience the same problem.

Now I know what you're thinking, but I absolutely don't want to re-board it. It's an ASUS P5N-D and it's only a year old, it shouldn't fail that badly.



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up vote 3 down vote accepted

It shouldn't fail that badly, but with power surges there is the potential that it could.

First of all, try these network cards in another machine. If these network cards you are trying work in another machine but not this one, then you most certainly have some kind of motherboard PCI fault. If they don't work in another machine then something in that machine is killing them and could be a faulty power converter or something.

It may even only be an intermittent fault whereby the first few packets of PCI data are transferred to the CPU and then after that the controller falls over. Heck it could even be a DMA controller problem. All these could have been cause by stray voltage that happened during the power surge. computers are highly sensitive devices and can die in literally thousands of amusing and frustrating ways.

The next thing to try would be a USB to Ethernet adaptor. If that works then the majority of the machine is good and you definitely have some kind of PCI problem. You might get away with this machine doing light duties but keep in mind that you may never be able to use PCI expansion cards in it.

If, after trying what I suggest above to no avail, you absolutely refuse to re-board the computer then I suggest you put it in a corner and ignore it.

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Thanks for the advice. I do have a spare motherboard that I think works, It's just a real pain to do as I have to re-install everything as well. I'll try the USB adapter, then re-board it as a last resort. – Hamish Milne Jun 16 '11 at 11:05

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