Detecting and allocating IRQs

I am interested to know what Diagnostic Software and Hardware people are using to detect and allocate IRQ resources in Windows 95.  I am curently having no end of trouble trying to find "Spare" holes to fit in all the required items in a friends computer and that is what made me thing of asking this of the Experts.  In my friends case it is a fairly recent Pentium motherboard with 2 onboard Comm Ports and one Printer port.  There is a PS/2 Mouse port and the machine is running a Matrox Milenium Card.  She has a Scanner with a Plug and Play SCSI Card.  A second Printer Port to run a Tape Drive.  An SMC EtherEZ Network Card and an AWE32 Sound Card.

Whenever all the Componants are installed the Network card fails and invariably the "Generic" SCSI PnP card for some reason does not always see the Scanner.  If I remove the Network Card or the Sound Card it all seems to work OK.