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What is 32-bit / 64-bit CPU?
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By Super Admin
Published on 06/30/2011
 
What is 32-bit / 64-bit CPU?

What is 32-bit / 64-bit CPU?
"32/64-bit" refers to the width of the address bus and registers used by the CPU core. A 64-bit CPU has a 64-bit wide address bus and 64- bit wide registers. CPUs access data in the RAM by using the address bus. The breadth of the bus influences the amount of RAM that can be addressed. A 32-bit bus allows a maximum of 4 GB of RAM to be accessed. A 64-bit CPU, obviously, allows for more RAM to be used - about 16 exabytes (1 exabyte = 1,000,000,000 gigabytes, approximately). A 64-bit register can store 64 bits of data simultaneously. To fully utilise a 64-bit CPU, the operating system and application need to support the 64-bit mode of operation.