Dell OptiPlex GX1 Dell OptiPlex GX1/GX1p Managed PC and OptiPlex NX1 Net PC S - Page 34

IRQ9 Available for use by an expansion card, except in ACPI-enabled configurations. IRQ10 Available for use by an expansion card. IRQ11* NIC/default PCI IRQ. IRQ12 Generated by keyboard controller to indicate that mouse's output buffer is full. IRQ13 Generated by math coprocessor to indicate coprocessor error. IRQ14 Generated by device connected to primary EIDE port to indicate that device requires service. If the EIDE controller is disabled, this line is available for other use. IRQ15 Generated by device connected to secondary EIDE port to indicate that device requires service. If the EIDE controller is disabled, this line is available for other use. * If an ISA expansion card is configured for IRQ11, the optional NIC or PCI IRQ is assigned to another available IRQ line. DREQ0 Available DREQ1 Available DREQ2 Generated by super I/O controller to initiate DMA cycle for attached diskette drive DREQ3 Available DREQ4 Generated by bus controller chip to activate second DMA controller DREQ5 Available DREQ6 Available DREQ7 Available NOTE: The built-in audio controller, NIC (optional), and video controllers are assigned available DMA channels automatically during system start-up. The following subsections provide service-related information about hard-disk drive options for the OptiPlex GX1/GX1p, and OptiPlex NX1 computers. NOTE: Throughout this manual, references to component locations assume the chassis orientations illustrated in Figure 1-15. 1-22