a nic might get away with sharing with something like usb but I never heard of 2 nics sharing with each other before so I am fairly certian that is the cause of your bsod. As mediator suggested the lan connection going down may well have helped trigger the bsod but wouldnt be the fault.

Right, yes it does seem odd.

The other NIC (another D-Link gigabit card) is on IRQ 21. That's connected to my daughter's PC.

I've tried changing the resource settings manually (i.e. untick 'use automatic settings'), but the option to do so is greyed out!

That particular problem may be because of a 'repair install' done about 8 months ago.

I have a feeling that the 'permissions' may have got screwed up a bit?

The inability to remove the automatic settings applies across the board i.e. to the sound card, graphics card, network adapters, everything.

Edited by BlobbyBlobby (Thu 26-Oct-06 16:56:11)

you wont be able to change the irq in windows you will need to swap the pci slot its in.

Not sure if we're at cross-purposes here, but 'automatic settings' is usually an indication that the BIOS is in auto-control of the resources, ie. of the assigning of the resources. So, it looks as though that's right, in your case. If you now try to change the IRQs manually, it won't work; it's not meant to.

This is obvious I know, and I may be misunderstanding your description, but because you're using a Speedtouch 546, the only NIC connection needed on YOUR PC is a single one. And the only NIC connection needed on YOUR DAUGHTER'S PC is also a single one.

Edited by deleted (Fri 27-Oct-06 17:48:45)

Yeah, slight misunderstanding meditator, but I didn't really explain properly.

Re the IRQ problem. I think the automatic settings being greyed out was there even when the BIOS wasn't handling the resource settings too. So, until I re-install WinXP again from scratch I won't be able to verify the permissions problem unless someone else can in the meantime.

Re the router. Well having had the 510v4 with 4 ports (and recently the 546v6) the 'obvious' solution is to let both kids have 2 of the spare ports on the router, right? WRONG!

The lil' so and so's stole ALL the bandwidth constantly with p2p uploading and downloading and spyware!

So, for the past 18 months or so they're connected via ICS using 2 D-Link Gigabit Ethernet NICS which each have a separate PCI slot.

My PC is connected to the router via the onboard (motherboard) Broadcom Ethernet controller. So, altogether there are 3 Ethernet controllers.

The Broadcom has been assigned IRQ 20 and is shared with one of the D-Link NICs. The other D-Link NIC has been assigned IRQ 21.

All the bandwidth control is done with BWMeter which strictly limits both of their upload AND download bandwidth. Internet heaven (for me anyway). LOL

Perversely, the graphics card IRQ shares with some USB controller!

Edited by BlobbyBlobby (Fri 27-Oct-06 18:17:12)

ouch the gfx shouldnt be sharing either not a very good motherboard by the sounds of it.

Go into your bios and see if there is an option for assignign a dedicated irq to the agp there normally is.

If possible also disable all usb functions in the bios, if you use usb you cant do this.

With the network card irq sharing it sort of works like this. The motherbaord will have hard irq values for different slots so 2 slots usually share with each other, anothe rslot will usually share with agp and another slot would usually share with usb, sometimes a slot will share with some other onboard device, for a pci card to have its own irq one would usually use one of the 2 pci slots that share with each other but not the other one. So You can probably only have one of the lan cards have its own irq but if the other shares with usb or something it should be ok just not a good idea to share with another lan card.

The bios may allow you to manually set the irq but it would be for the IRQ line not just for the lan card itself so what would happen is you change the irq for both lan cards together and they would still be sharing, this is why the only way to solve the conflict is to open the case and physically switch the card. If you want to use ICS tho there is no need to have 3 lan cards, you could cut it down to 2 by attaching a simple hub to the 2nd card and then the family pcs into that hub, it may be possible to switch it down to 1 by having them all in the broadband router, disabling nat on the router so only your pc has the internet access and ip then using ics from that to the family pcs with the brodband router also acting as a hub but that may not be possible I have never tried that kind of setup.

I don't altogether agree with what you say, Chrysalis.

Unless Microsoft have recently changed things, the BIOS will be automatically in charge of system resources (and therefore the allocation of IRQs) when the PC is set up as an ACPI machine, which is the default condition for PCs produced in recent years. Although you can change to a certain degree which PCI card uses which IRQ, you can do this only by trial-and-error repositioning of the cards in the PCI bus and the results are limited because they'll be what the BIOS decides, not you, the user.

Attempting instead to set IRQs manually, via the BIOS, usually fails, simply because the PC is running as an ACPI machine. Expand "Computer", in the Device Manager listings. The only way you can assign IRQs manually is to change the hal format, which would mean changing the Computer from an ACPI machine to a straighforward machine. This will be possible only by reinstalling the operating system and intervening in the initial setup (F6 or some such key, I think) to ensure that the machine isn't auto-configured as ACPI.

Provided the rules have been followed and you've enough memory to go round, IRQ sharing is not necessarily a bad thing. IRQ sharing doesn't automatically lead to blue screens and the like.

As for the sharing of the AGP graphics card's IRQ, again that's often found to be so, with any USB controller that's in use. But that's not automatically bad. I recently added more USB ports myself, via the PCI bus, and have ended up with my AGP card's IRQ being shared. But no problems have arisen as a result.

You not disagreeing with me at all, some bioses but very few allow manipulation of irq addresses but tweaking these settings often doesnt change anything in terms of irq conflicts as you just suggested.

Windows can use the bios irq values or it cannot, some bioses have a value allowing the toggling of a pnp os yes/no this is what I believe allows windows to set its own irq values or not. However even if windows can set its own irq values it will still be limited by the irq value in the hardware, have you heard inta intb intc intd values? Sometimes these are adjustable in the bios and are at least usually documented in the motherboard manual.

They are 4 hard wired irq paths usually shared between a dozen or so devices so many of them will always be sharing, often usb, raid controllers and onboard sound devices share with 1 or 2 pci slots, agp shares with another pci slot, and 2 pci slots share with each other. Thats why when you try doing things like disabling com ports and lpt ports the pci devices dont move to the new empty irq because it cant. However changing the HAL type affects this behaviour.

APM doesnt support irq sharing so this is the most likely configuration that would allow any type of irq manipulation in windows, and if you remember the ms dos days soundcards etc. irq value could be adjusted after bootup. ACPI which most pcs use utilises irq sharing based on the four int values and APIC I am not sure how it works but opens up new higher irq numbers and supports ACPI features, however I have noticed on APIC like ACPI irqs cannot be changed in windows and devices often still share with each other with many irqs sitting unused, it can sometimes stop devices sharing an irq over an ACPI configuration but I believe they will still be sharing the hardwired int value.

TO change the HAL as you said it involves formatting the pc and pressing F6, much much easier to open the case and move the card to another slot which seems to have left the OP stumbled.

Yup, I agree.

There is nothing wrong with having 2 NIC's in a PC. What you want to avoid is sharing a busy interrupt, like USB.