I'd try newer drivers first, and remember, if you're installing driver updates in Windows 2000, it's usually better to choose the "List all Drivers for this Device" option when upgrading, then choosing "Have Disk". Otherwise, Win2k might arbitrarily decide that your upgraded drivers are no better than your current ones and refuse to install them.
Otherwise, please know that it's apparent that your PC is setup in Windows 2000 to use ACPI Power Management.
ACPI uses IRQ9 to "steer" all PCI Plug n Play devices to various IRQ's. Note that even without ACPI installed, it's usually not possible to change IRQ resources AFTER a device has been installed. Microsoft says it's because Win2K has so much more to consider and manage than Win9X where hardware is concerned that it's not able to juggle changes in resources (IRQ's and I/O resources) after a device has been installed. So, chances are that even without ACPI, your hardware's resources cannot be altered.
There IS a way to disable ACPI on PC's in Win2K after Win2K installation. Note that MS does NOT support this, but I can tell you that I have a friend who used it successfully without problem. The funny thing is is that without ACPI installed, he now shows IRQ's in the 30's, like IRQ 36 for his sound card, etc. Win2K can create these virtual IRQ's...ya just never see them when ACPI is enabled as most show as IRQ9.
Here's the link. Do the normal backup of data and programs before doing it.
HOW TO DISABLE ACPI IN WINDOWS 2000 AFTER INSTALLATION...USE AT OWN RISK