That depends on how platform gets defined. At the OS layer, a reasonable argument could be made for (cpu, northbridge, southbridge). Of course the whole northbr

That depends on how platform gets defined. At the OS layer, a reasonable argument could be made for (cpu, northbridge, southbridge). Of course the whole northbridge thing can actually not include usb support, or disk io support, which can then throw more multipliers in there based on chip... Sure there are standards to describe hardware interactions, but any reasonably experience sysadmin will tell you horror stories of when they found a weird issue with chipset X not following the standard just right, and needing a special case driver that no longer worked with the OS of choice. This means there are combinatorial multipliers on a per device basis (or some percentage thereof...)