Lost network card - Solved

[James Wilkinson]

Claude Jones wrote:
> I have a fairly brand new install of FC3 with all the latest
> patches. I replaced the on-board video with a Radeon 9200, today.

AGP or PCI? I'm guessing PCI...

> When I came back up, the machine couldn't find the network card.
> It comes up inactive and it says it does not appear to be present
> if I try to activate it with the Network Configuration utility. If
> I remove it from the configuration in the same utility, Kudzu
> doesn't redetect it.

... snip ...

> I solved this by deleting it in the Network Configuration utility, and 
> shutting down, removed the card, then restarted; Kudzu detected it was 
> gone and removed it; I rebooted back to the desktop, then shut down and 
> reactivated the NIC (it's a built-in configured on/off with BIOS 
> settings); when I came back up, Kudzu recognized it and let me configure 
> it.
> 
> Since this happenned right after installing the new video card, is it 
> safe to suspect that the new video card created an IRQ or other 
> resources conflict?

"Probably." I'm slightly surprised that Windows worked OK.

My experience has been that the Radeon 92x0's PCI implementation is
finicky. A couple of PCI boards (I only had one in at a time) didn't
want to work at all in a BX-based motherboard. They didn't even start to
display anything, the computer didn't even beep, and it certainly didn't
POST.

I've a suspicion that was because the BX had PCI version 2.1, while the
Radeon expected 2.2. But I've never seen another otherwise-working card
that will do that.

Even on newer boards, I had problems getting the Radeon to work.

PCI has its own IRQ scheme: IRQs are labelled IRQ A to IRQ D. All four
IRQs are available to each slot, but the order in which they are used
varies. If you have more than four PCI slots *and* add-in PCI devices on
the motherboard, some of those IRQs will be shared. If you have PCI
devices that need more than one PCI IRQ (and I believe the Radeon does),
then some of those IRQs will be shared. And the Radeon appears to be
less than happy with sharing at least one of those IRQs.

I don't know what your motherboard is like. It may be that disabling the
NIC and re-enabling it changed something about the way the board handles
resources. It may be that getting Kudzu to redetect it and re-enable it
after a reboot meant that it chose different resources. A
"before-and-after" view of your /etc/modprobe.conf file could be
enlightening.

If your card is AGP, then that should take the IRQs out of the equation.
In which case, I'd guess the most likely candidate was where on-board
memory was mapped: it could be that the extra memory of the Radeon was
mapped "over" the network card's buffer, and the remove / reboot /
redetect cycle mapped the buffer somewhere else. And I wouldn't have a
clue why the network card could "move" its buffer and the Radeon
couldn't.

But in my experience, yes, it's safe to blame the graphics card.

Hope this somewhat rambling post illuminates more than it confuses!

James.

-- 
E-mail address: james | When did you last back up your system?
@westexe.demon.co.uk  |