Odd NIC Problem

[Steve Parry]

One of our PC's started having a regularly disabled NIC (few times per day).
As soon as the user manually enables it it works properly, until the next
random time it disables itself.

When not disabling itself it seems to work normally. It's not showing as
disconnected the NIC is being disabled exactly as if you manually disable it
within device manager.

It's not an OS issue or a PC issue because I've swapped out the original
2000 PC with a brand new XP Pro one, this exhibitted exactly the same probs.

I've tried patching the users network socket to another port on the switch.
Other users in the same office, on the same switch don't have problems.

I've also tried changing the PC to wall socket cable.

My only thoughts now is there maybe some wiring issue with the wall socket,
but quite how the NIC is getting disabled I'm not sure. Could the NIC's be
shutting down to protect themselves from some voltage spikes maybe :S

I've never seen a NIC do this before so all suggestions welcome!

 

[Pegasus \(MVP\)]

One of our PC's started having a regularly disabled NIC (few times per day).
As soon as the user manually enables it it works properly, until the next
random time it disables itself.

When not disabling itself it seems to work normally. It's not showing as
disconnected the NIC is being disabled exactly as if you manually disable it
within device manager.

It's not an OS issue or a PC issue because I've swapped out the original
2000 PC with a brand new XP Pro one, this exhibitted exactly the same probs.

I've tried patching the users network socket to another port on the switch.
Other users in the same office, on the same switch don't have problems.

I've also tried changing the PC to wall socket cable.

My only thoughts now is there maybe some wiring issue with the wall socket,
but quite how the NIC is getting disabled I'm not sure. Could the NIC's be
shutting down to protect themselves from some voltage spikes maybe :S

I've never seen a NIC do this before so all suggestions welcome!

As you suggest, the only thing you haven't replaced is the
cabling in the wall. This suggests a noisy or spikey signal,
causing the NIC to shut down. A poorly terminated connection
might be responsible. You can easily prove or disprove it
by stringing a temporary CAT5 cable across the floor.

 

[Stubby]

As you suggest, the only thing you haven't replaced is the
cabling in the wall. This suggests a noisy or spikey signal,
causing the NIC to shut down. A poorly terminated connection
might be responsible. You can easily prove or disprove it
by stringing a temporary CAT5 cable across the floor.

I believe NICs have an "anti-jabber" circuit that is supposed to turn
off the send-side if there is a continuous collision detection
condition. So, the source of the problem may be another computer on the
same switch.

 

[Steve Parry]

I believe NICs have an "anti-jabber" circuit that is supposed to turn
off the send-side if there is a continuous collision detection
condition. So, the source of the problem may be another computer on the
same switch.

good thought, only fly in this ointment I can see is there's others on this
same switch so would think others may experience.