Technical & Support

PCI-PCMCIA

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Please Note... the information contained in our support pages is accurate to the best of our knowledge and belief, however Elan cannot accept responsibility for non-operation in any specific configuration.

Multiprocessor Machines (SMP)

The P-Series range of adaptors cannot fully support multi-processor operation. This is because of problems with the BIOS. 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 1410/1420 models (P111/P222/P423)

Affected Systems

This problem affects all machines running Intel hyperthreading technology. Many of these machines do not have BIOS-s that correctly allocate resources (see below for more information). Machines running hyper-threading include :

Multi Processor machines, e.g. dual processor
Some dual processor motherboards even if only 1 processor is fitted
Multi Cor machines (where one chip effectively contains more than one processor)

This problem affects all Windows NT operating systems including "Server 2003", XP and Vista.

If you are not sure whether your machine will be affected, you can look at the system information by clicking 'Start', and then 'Run', and typing 'MSINFO32.exe' into the box that comes up. The header (front) screen gives basic information about your system.

Motherboards reported as working with a P-series:

HP Kayak XU800, Bios IA 11.10
ASL Marquis C250S system = Tyan S1867 Thunder 2500 motherboard with dual Pentium III 1 GHz Coppermine processors (see www.aslab.com)
Celsius 620 with Systemboard Siemens D1161-A100
Celsius-R 610 with Systemboard Siemens D1357
Dual 1G, PIII, HP Kayak, XM600, Series 2, under Win 2k / SP 3, BIOS 11.11

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:

ACPI Multiprocessor PC
MPS Multiprocessor PC
MPS Uniprocessor PC