A Semi-inserted PCI-X card in a 32-little bit PCI slot, illustrating the need to the rightmost notch and the extra room over the motherboard to remain backward appropriate PCI provides individual memory and memory-mapped I/O port address spaces for that x86 processor family, 64 and 32 bits, respectively. Addresses in https://nathanlabsadvisory.com/maximize-business-trust-and-security-with-hitrust-compliance/