Hardware Question

[Darren Mansell]

On Tue, 2007-07-31 at 05:24 -0600, Donald D Henson wrote:
> For any of you hardware experts out there...
> 
> 1. Does i686 always mean that the referenced processor/machine/platform
> is 64-bit?
> 
> 2. Does i386 always mean 32-bit?
> 
> 3. If the 'uname' command reports that the machine/processor is i686 and
> that the platform is i386, does this mean that I am restricted to 32-bit
> software?
> 
> I think I know the answers to these questions but I'm not sure, and I
> haven't been able to find an answer for such basic questions. Thanks for
> any assistance.
> 
> -- 
> Donald D. Henson, Managing Director
> West El Paso Information Network
> The "Non-Initiation of Force Principle" Rules
> 
> 

Hi Donald,

in the absence of more accurate knowledge heres my take:

i386, 486, 568 and 686 refer the architecture of the processor and the
way it works. Software compiled for x86 (which means any of 386, 486
etc) will not work on other processor architecture such as PowerPC
(MAC), SPARC or Cell

i386 is the standard base x86 CPU that modern software is compiled for
so in theory it should work on any processor from i386 upwards. The 486
had more features and were around 66Mhz, 100Mhz and 133Mhz. The Pentium
then gave us the i586 as it had more features again. Finally IIRC the
Athlon K7 and Intel Pentium3 were the first processors to be deemed i686
so if software wants to take advantage of the extra features these CPUs
provide they compile for i686.

64-bit is still x86 compatible but software can be written to take
advantage of the extra performance it provides. so 64-bit is 386 and 686
(generally called x86-64) but the modern 64-bit CPU's are all 686's

Hope this isnt too far off.