Looks like I am having a good old fashioned IRQ conflict. Even though
IRQ's are theoretically shareable these days, in practice it may not be
such a hot idea. The problem first occurred after I replaced my
motherboard and processor on one of my systems, a couple of weeks back.
I was getting a BSOD once every couple of days. I have had 5 BSODs so far.
There has been 3 different types of Stop messages: variously involved
the DRIVER_IRQL_NOT_LESS_THAN_OR_EQUAL (twice), the BAD_POOL_HEADER
(twice), and the UNEXPECTED_KERNEL_MODE_TRAP (once) errors.
Initially, they involved TCPIP.SYS and IPNAT.SYS, both of which were
network-related. So I thought it is a network card issue and I updated
the Realtek Gigabit Ethernet driver, but that did not help.
Then a couple of days ago, I got another BSOD, but this time it involved
the driver NV4_MINI.SYS, which is an Nvidia video card driver -- seemed
completely unrelated. Then earlier today, I got another
DRIVER_IRQL_NOT_LESS_THAN_OR_EQUAL error, and this time it came from
both the TCPIP.SYS and the NV4_MINI.SYS drivers together! That clued me
into the idea that perhaps these two are sharing the same IRQ. I looked
in Device Manager, sorted it by Resource Connections, and sure enough
the gigabit ethernet and video card are both sharing IRQ 18! And that is
not all, there is 5 other devices sharing this same IRQ too! Seven
devices on the same IRQ line! There is only one other line, IRQ 16, that
has multiple devices on it too, at comparatively paltry 3 devices. Every
other IRQ line that is used only has one device on it, and there are
several empty unused IRQ lines all over the place.
So I went into the BIOS settings, but could not find any IRQ setting
functions available to it. The only option I found was something that
either enabled or disabled Plug'n'Play OS support, but not much else.
I tried to go into Windows' Device Manager to manually configure the
IRQ's, but the manual setting of resources was grayed out. According to
this webpage, you cannot manually set anything inside an ACPI-compliant PC:
automatic settings will be greyed out), this is usually related to the
ACPI function used by Win XP. "
So now I am stuck, is there isome kind of program available to reset the
ACPI tables? Some sections of the Registry that I can change?