The data path size for a 64-bit processor is 64 bits. This means it supports memory addresses, integer sizes and data paths that are 8 octets wide.
SIMMs have a 32-bit data path.
SIMMs have a 32-bit data path DIMMs have a 64-bit data path
Generally, the bit size of a processor is indicated by the size of the accumulator, which is, most times but not always, the same as the internal data bus size. The 8086/8088 processor, for instance, is a 16 bit processor. The 8085 is an 8 bit processor. The 80386 is a 32 bit processor. The Q6600 Core2 Quad is a 64 bit processor. (These are just examples.)
The width of a data bus is referred to as the data path size. An example would be a 16 bit bus can transmit 16 bits of information
The 8086/8088 processor is called a 16 bit processor because its basic architecture is 16 bits wide. Its registers and accumulator are 16 bits wide, and the primary data it manipulates without extra work is 16 bits wide.
Not necessarily. In the 8085, for instance, this is true. In the 8088, however, the processor is a 16 bit processor with an 8 bit data bus. The same is true for the 80386sx - it is a 32 bit processor on a 16 bit bus.
64 bit
Real mode uses 16 bit data path while protected mode uses 32 bit data path.
A 32 bit processor has 32 bit wide data bus while a 64 bit has 64 bit wide data bus. Address bus may or may not be 32 bit or 64 bit wide in the respective processors. To fully utilise the 64 bit data bus the programs must be written in such a way that they can use 64 bit wide data bus. A 64 bit processor can also act as 32 bit.
64-bit data path and rambus technology
The memory unit's size that depends on the processor is the bit.
bit size is a wordlength of one memory location