difference between 32-bit and 64-bit processor?

[Poseidon]

Hi guys..

I was just wondering what exactly the difference is between 32-bit processors and 64-bit processors is (ok, they're probably faster..)? And is there difference in machine code per processor?

Thanks.

[Brendan]

Hi,

Hi guys..

I was just wondering what exactly the difference is between 32-bit processors and 64-bit processors is (ok, they're probably faster..)? And is there difference in machine code per processor?

Basically, all 32 bit software will behave as expected (it's fully backward compatible). There is an additional "64 bit" mode (called "long mode" by AMD) that needs to be used to gain anything from the extra features.

See the Wiki: http://www.osdev.org/osfaq2/index.php/T ... s%20CPU%20...

You can also download full details from both AMD and Intel...


Cheers,

Brendan

[Pype.Clicker]

AMD 64bits have "no execute" page bit, they have a new multi-level paging system, they no longer support segments in "long mode", and they have the long-awaited "rip-relative" addressing mode.

And probably much more

They have larger register set too (15 general-purpose 64 bits, some being aliased to "rax, rbx, ...").

...

and of course they allow 64bits addresses

In legacy mode, they're pretty much indistinguishable from their 32 bits counterpart ...