Switch Killed Computer's LAN port

I connected a Asound 8 port switching hub to my network and one of the computers suddenly could no longer communicate over the LAN. It couldn't get an IP address. I verified that this is not a software problem by swapping the hard drive and OS from an identical computer. I installed another LAN cards in this computer and it now work fine with the same cable, etc. The problem port is an on-board port on a Biostar M7NCG motherboard. I've reset the CMOS, but that didn't help. The problem port's lights come one when the cable is plugged in, but it will not acquire an IP address. It also will not communicate when I set a static IP address. The NIC appears fine in Device Manager. The port has been working fine for the last three months right up until I installed the switching hub. It appears the switch caused the problem. However, other computers connected to the switch were not affected and the switch appears to be working fine. I've installed a LAN card in the problem computer and all is well, but this has me wondering.

What could cause this problem? Is it possible that the switch is defective and it sent out an electrical current that damaged the port? I'm concerned that the switch could cause more problems. Is there a way to test a switch's LAN port to check its electrical characteristics?

Thank you, Steve Smith

Reply to
Steve Smith
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Two quick tests.

Does that computer work in other switch ports? Does that port work with other computers?

It's unlikely that any device damaged another. The voltage required to do that, simple does not exist on the NICs and they're also connected to the line via transformers, so there's no direct connection, between devices.

Reply to
James Knott

No, the computer's problem port does not work in other switch ports or when connected directly to the router. Other computers and other LAN cards in this computer work just fine on the same cable and switch port.

The problem is definately with the computer's onboard LAN port. Perhaps it was just a coincidence that the port died when I connected it to the new switch. Any other ideas?

Thanks, Steve Smith

Reply to
Steve Smith

What do the lights on the NIC show? What does the operating system show for status?

Reply to
James Knott

sh*t happens. It's possible that the pins on the RJ45 socket have been damaged. IMO you can't blame it on the switch.

I assume you've tried a known-good cable, etc.

Reply to
Al Dykes

The lights on the NIC light up just as they did before the problem. Also, another identical computer has the same lights. Windows XP Pro shows that the NIC device is operating correctly, but it also shows that it has limited or no connectivity. I'm using the same cable with another NIC and that NIC and cable work fine in this computer. I guess Al Dykes is right, "sh*t happens".

Steve Smith

Reply to
Steve Smith

I had a lightning strike about a year ago, hopped on the network, and over half the ports on a 24+2 switch got zapped. In many cases, the downstream NICs got zapped as well. In a couple cases the NIC got zapped, but the port on the switch was still ok, and vice versa. So, it's possible, but perhaps much less so under normal circumstances.

:-)

Reply to
Randy Howard

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