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Multiprocessor Machines (SMP)

Currently the P-Series range of adaptors cannot fully support multi-processor operation.  In some systems a P-series adaptor will work, but this cannot be replicated in all systems and it is not possible to determine in advance from system information whether a P-series adaptor will work or not - you just have to try!

The legacy models (Cirrus Logic chipset based) CANNOT be made to work with a multi-processor motherboard. You will need to try one of our TI models (P111/P222/P423)

Motherboards reported as working with a P-series:

If you have a multiprocessor machine working with a P-series please let us know so that we can add your system here!

More information:

In a multi-processor PC, Windows NT & 2000 uses the IOAPIC to assign interrupts from the PCI bus, based on information provided by the BIOS.

CardBus adapters are usually enumerated by the BIOS as PCI to CardBus bridges and as such most BIOS's consider them as not requiring an IRQ.
During the initial boot process, Windows stores this IRQ routing information, and it is not re-configurable, so when the PSeries driver loads, this decision not to assign an IRQ to the CardBus adapter has been set in stone.

For correct operation, the PSeries and PCMCIA drivers require an IRQ to be assigned for card status change etc. In the Uni-processor kernel, IRQ's are not routed through the IOAPIC, so if the BIOS has not assigned an IRQ, the PSeries driver is able to route an IRQ through to the hardware without any problems.

NOTE that this FAQ also applies to multiprocessor motherboards with only one processor fitted if the following Windows NT4.0/2000 kernels are installed: