From: Pavel Machek on
On Thu 2010-05-27 20:59:07, Len Brown wrote:
> > > ... we think we can do better than ACPI.
>
> > Why exactly? Is there any info missing in the ACPI tables?
> > Or is this just to be more independent from OEMs?
>
> ACPI has a few fundmental flaws here. One is that it reports
> exit latency instead of break-even power duration.
> The other is that it requires a BIOS writer to
> get the tables right.
>
> Both of these are fatal flaws.

Intel is co-author of ACPI spec, right? So what about fixing those?

> > > Indeed, on my (production level commerically available) Nehalem desktop
> > > the ACPI tables are broken and an ACPI OS idles at 100W. With this
> > > driver the box idles at 85W.
>
> > What exactly was broken there?
>
> Dell's BIOS developer botched a bug fix immediately before the system
> went to market and disabled support for all ACPI C-states except C1.
> After several month of shipping systems, they still were unable
> to ship them with a fixed BIOS.

I always thought that cpu vendors have ways to work with bios manufacturers...

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