IRQ problem with a new SBS 2000 Server installation
I have an IRQ problem with a new SBS 2000 Server installation for use in-house and for testing/training. The NIC reports in Device Manager as IRQ 16 and the SCSI Controller reports as IRQ 17. Both devices are stated to be functioning correctly with no conflicts. MS Help states that there are only IRQs 1-15, so how do we get 16 & 17 reported?
We have IRQs 5, 7, 10, 11 all free on the system. I have tried to force the IRQs in the BIOS setup for the respective PCI slots to 7 for NIC and 11 for the SCSI card. But although they get recognized correctly when the system initially boots, once Win2K loads, the Device Manager puts them back at 16 & 17. Any helpful suggestions or fixes?
Motherboard is GigaByte GA-6VXT with P3-933 proc, 2 x 256 MB ECC SDRAMs, TEKRAM DC-390-U2W scsi card, IBM 9GB LVD 68pin for C-drive and Quantum Atlas 18GB lvd 68 pin for D (data) drive, D-Link 530 tx NIC.
Your motherboard probably offers IRQs through 22 or so, even though the OS only really recognizes the first 15. You should closely inspect your motherboard documentation and even contact the vendor; the higher order IRQs are usually shared and this can cause havok with many devices (especially bus-mastering cards). You may need to assign IRQs manually to PCI bus slots via the CMOS and in each expansion card's BIOS.
This was first published in February 2002