Re: BIOS, Duron4 specifics...

[ebiederm@xmission.com (Eric W. Biederman)]

John Clemens <john@deater.net> writes:

> On Tue, 10 Jul 2001, Dave Jones wrote:
> 
> > On Tue, 10 Jul 2001, John Clemens wrote:
> >
> > > I've got a new laptop with an AMD Duron in it, based on the Athlon4 core
> > > (PowerNow, SSE, hardware prefetch, etc.. Palomino core)..  However, it
> > > appears none of the useful features are enabled in the bios.  For example,
> > > Nowhere does it appear to enable SSE or the APIC.
> >
> > afair, the mobile Durons are not based upon the Athlon 4 core, and
> > hence won't have the features you mention. You can verify this with
> > my x86info tool which you can get from
> > ftp://ftp.suse.com/pub/people/davej/x86info/x86info-1.3.tgz
> 
> Actually, CPUID reports Family 6, Model 6, Rev2, which corellates directly
> to Athlon4/MP (Model 6) processors.  Whats surprising is that is doesn't
> report model 7, which AMD claims is supposed to be the mobile Duron ;)..
> make me wonder if it's really a neutered Athlon4.  Besides, I though the
> origional mobile durons (T-bird core, model 3) didn't even support
> powernow...?

To enable SSE you have to write a bit into a undocumented register.
For the APIC the procedure to enable it is the same as the P6 core.

Eric