[CentOS] Centos 5 on i586

[Mark A. Lewis]

-----Original Message-----
From: centos-bounces at centos.org [mailto:centos-bounces at centos.org] On
Behalf Of Garrick Staples
Sent: Friday, February 08, 2008 4:32 PM
To: CentOS mailing list
Subject: Re: [CentOS] Centos 5 on i586

On Fri, Feb 08, 2008 at 12:40:55PM -0800, MHR alleged:
> On Feb 8, 2008 9:02 AM, Ray Van Dolson <rayvd at bludgeon.org> wrote:
> >
> > On Fri, Feb 08, 2008 at 05:47:58PM +0100, Matias Surdi wrote:
> > > Is possible to install Centos 5 on a 586 CPU? (cpu_type = 5)
> > >
> >
> > No.  I think there was some interest in making this happen at some
> > point:
> >
> >  http://wiki.centos.org/QaWiki/CentOS5PentiumSupport
> >
> > However I'm not sure that it will end up happening:
> >
> >  http://bugs.centos.org/view.php?id=1836
> >
> 
> Pardon me, but you CAN install CentOS 5.1 on any x86 CPU.  If your CPU

> is a valid 64-bit CPU, you can install either the i386 version
> (32-bit) or the x86_64 version.  You may not get full support of 
> specific CPU instructions that are available ONLY on your particular 
> CPU, but the right one will run.
> 
> I had 586 CPUs on two different machines at work way back when 5.0 
> came out, and the x86_64 installation ran just fine on both.

>There is no such thing as a 64bit i586 CPU.
>
>With regards to Intel CPUs, the original Pentiums are i586.  Everything
after that (PentiumPro, PentiumII, III, and IV) is i686.  Earlier
PentiumIV are >32bit only, later chips added the 64bit instructions and
registers.
>
>The CPUs are backwards compatible with older software.

So, what is a "valid" 64bit CPU? I have a DEC Alpha in the basement that
is most certainly 64 bit, but can't install the i386 or x86_64 version
on it. How about Sparc or HP-UX boxes? Are they valid 64 bit CPUs?