what doesnt determine the amount of physically addressed memory inside a computer?

Question

Processor physical address lines,

Memory bus width,

virtual address space,

amount of RAM

can anyone tell me which of the above is correct? i've been puzzling this for days and can't find anything concrete that gives me the answer :(

Answer 1

Memory bus width has nothing to do with how much memory is addressable. It just indicates how many bits can be transferred in parallel.

The others relate all, in some way, to the total amount of memory that can be addressed by the CPU/memory controller.