One bit in the register can reference an individual byte in memory, so a 32-bit system can address a maximum of 4 GB (4,294,967,296 bytes) of RAM. The CPU register stores memory addresses, which is how the processor accesses data from RAM. Most computers made in the 1990s and early 2000s were 32-bit machines. In short, any amount of memory greater than 4 GB can be easily handled by it. For instance,Ī 32-bit system can access 2 32 different memory addresses, i.e 4 GB of RAM or physical memory ideally, it can access more than 4 GB of RAM also.Ī 64-bit system can access 2 64 different memory addresses, i.e actually 18-Quintillion bytes of RAM. These types of processors tell us how much memory a processor can access from a CPU register. In computing, there are two types of processors existing, i.e., 32-bit and 64-bit processors.