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Windows 95 OSR2 (B/C) Fails to Allocate Resources to the PC-Card

Symptoms:

The PC-Card is recognised by the operating system, but it fails to automatically allocate any resources to it, even though the resources may be available and a yellow exclamation mark (!) appears over the PC-Card in the Device Manager.

More Information:

Windows 95 uses the BIOS IRQ routing table for IRQ routing information. As some modern motherboards do not have ISA bus slots, ISA bus interrupts are not "available". This poses a problem with routing an "ISA style" IRQ to a 16-bit PC-Card in a PCI based PC-Card adapter. 

This problem has been seen on an ABIT Intel 815e chipset motherboard when using a P111 adapter with the IBM Microdrive, but is quite likely to happen on other motherboards (without ISA slots) and with other PC-Card types in Windows 95.

Solution:

First of all, check that PCI IRQ routing is enabled and working correctly (see "PCI IRQ routing in Windows 9x").

Then you must manually assign all the resources to the PC-Card. If your PC has no spare IRQ's available, the trick is to assign an IRQ assigned to a PCI device (one marked "IRQ holder for PCI steering"). This will force Windows to move the IRQ for the PCI device onto another IRQ (PCI devices can share IRQ's with other PCI peripherals). 

Alternatively, use the BIOS to reserve an IRQ from being allocated to a PCI device (you must consult your motherboard manuals on how to do this), then manually allocate this to the PC-Card you are using.