Asus P I-P55SP3AV P/I-P55SP3AV User's manual - Page 46

Software Guide PNP(Plug AndPlay) The seven "IRQ ... Used By ISA" lines indicate whether or not the IRQ indicated for each line is being used by a 'legacy'(non-PNP) ISA card. The default setting "No/ICU" indicates either that the IRQ is not in use by the ISA Bus or that an ISA Configuration Utility (ICU) is being used to determine if an ISA card is using that IRQ. If you install a legacy ISA card that needs a specific IRQ, and you are not using an ICU, you must set the line for that IRQ to "Yes". For example, if you install a PNP ISA card that needs to use IRQ 3, you would set the "IRQ 3 Used By ISA" line to "No/ICU". If, however, you install a legacy ISA card that needs to use IRQ 3, and you are not using an ICU, set the "IRQ 3 Used By ISA" line to "Yes". The three "DMA ... Used By ISA" lines indicate whether or not the DMA chanel listed is being used by a legacy ISA card. The default setting "No/ICU" indicates either that the DMA channel is not in use by the ISA Bus or that an ICU is being used to determine if an ISA card is using that IRQ. If you install a legacy ISA card that needs to use a specific DMA channel, and you are not using an ICU, you must set the line for that channel to "Yes". If you have a legacy ISA card that uses any memory segment in the C800h to DFFFh address range and you have not used an ICU to specify the range it uses, you should set the base address and block size by using the "ISA MEM Block BASE" line. When you select a base address from the six options, the "ISA MEM Block SIZE" line will appear and you can select a block size from the four optioris. If you use an ICU to accomplish the same thing, leave "ISA MEM Block BASE" on the default "No/ICU" setting. If you have more than one legacy ISA card that needs to use this address range, you can increase the block size as necessary. 3-19