PA-RISC computers used the PDC for Boot ROM.| www.openpa.net
PA-RISC computers used error codes on their LED panels to signal system problems.| www.openpa.net
PA-RISC computers used proprietary HP expansion cards for EISA, GSC and PCI.| www.openpa.net
PA-RISC computers used many standard SCSI controllers and chips, mostly from NCR.| www.openpa.net