AMD Dual Core vs. Quad - Power Management

AMD Dual Core vs. Quad - Power Management

[Marc Perkel]

Been running a few tests and an AMD motherboard booting 2.6.25 from flash uses 0.33 amps if the CPU is a AM2 Athlon 6000. But if I used a Phenom Quad core CPU 9550 it pulls 0.55 amps.

In theory the 9550 should pull less because it's a lower TPD and the phenom processor is supposed to be smarter about power management.

So - why is the Phenom pulling more power? Is it because power management software for the Phenom isn't updated yet?

Marc Perkel
Junk Email Filter dot com
http://www.junkemailfilter.com


      

Re: AMD Dual Core vs. Quad - Power Management

[Alistair John Strachan]

On Tuesday 17 June 2008 23:00:25 Marc Perkel wrote:
> Been running a few tests and an AMD motherboard booting 2.6.25 from flash
> uses 0.33 amps if the CPU is a AM2 Athlon 6000. But if I used a Phenom Quad
> core CPU 9550 it pulls 0.55 amps.
>
> In theory the 9550 should pull less because it's a lower TPD and the phenom
> processor is supposed to be smarter about power management.

Not all 6000+'s have the same TDP. Maybe you have an F3 stepping 6000+ which 
has an 89W TDP, lower than a quad core Phenom (which is 95W only AFAICT).

Doesn't really explain the power gulf, though.

-- 
Cheers,
Alistair.

137/1 Warrender Park Road, Edinburgh, UK.

Re: AMD Dual Core vs. Quad - Power Management

[David Rees]

On Tue, Jun 17, 2008 at 3:00 PM, Marc Perkel <mperkel@yahoo.com> wrote:
> Been running a few tests and an AMD motherboard booting 2.6.25 from
> flash uses 0.33 amps if the CPU is a AM2 Athlon 6000. But if I used a
>  Phenom Quad core CPU 9550 it pulls 0.55 amps.
>
> In theory the 9550 should pull less because it's a lower TPD and the
> phenom processor is supposed to be smarter about power management.
>
> So - why is the Phenom pulling more power? Is it because power
> management software for the Phenom isn't updated yet?

At idle with CoolNQuiet on, all AMD processors seem to pull close to
the same amount of power, varying between 7-11 watts. Except for the
quad core processors, which pull significantly more at idle w/CnQ on
than dual and single core processors.

Tom's hardware has a nice chart listing power consumption here, all
his testing was done under Windows. His tests show the Phenom pulling
about twice the power of the Athlon64 X2 6000+ which matches up pretty
closely to your numbers.

http://www.tomshardware.com/reviews/amd-power-cpu,1925-7.html

Sounds like a question for AMD. The Phenoms seem to be pretty good
except for the extra 10-11w of power draw at idle which is
disappointing.

-Dave

Re: AMD Dual Core vs. Quad - Power Management

[Marc Perkel]

Marc Perkel
Junk Email Filter dot com
http://www.junkemailfilter.com


--- On Tue, 6/17/08, David Rees <drees76@gmail.com> wrote:

> From: David Rees <drees76@gmail.com>
> Subject: Re: AMD Dual Core vs. Quad - Power Management
> To: mperkel@yahoo.com
> Cc: linux-kernel@vger.kernel.org
> Date: Tuesday, June 17, 2008, 4:26 PM
> On Tue, Jun 17, 2008 at 3:00 PM, Marc Perkel
> <mperkel@yahoo.com> wrote:
> > Been running a few tests and an AMD motherboard
> booting 2.6.25 from
> > flash uses 0.33 amps if the CPU is a AM2 Athlon 6000.
> But if I used a
> >  Phenom Quad core CPU 9550 it pulls 0.55 amps.
> >
> > In theory the 9550 should pull less because it's a
> lower TPD and the
> > phenom processor is supposed to be smarter about power
> management.
> >
> > So - why is the Phenom pulling more power? Is it
> because power
> > management software for the Phenom isn't updated
> yet?
> 
> At idle with CoolNQuiet on, all AMD processors seem to pull
> close to
> the same amount of power, varying between 7-11 watts.
> Except for the
> quad core processors, which pull significantly more at idle
> w/CnQ on
> than dual and single core processors.
> 
> Tom's hardware has a nice chart listing power
> consumption here, all
> his testing was done under Windows. His tests show the
> Phenom pulling
> about twice the power of the Athlon64 X2 6000+ which
> matches up pretty
> closely to your numbers.
> 
> http://www.tomshardware.com/reviews/amd-power-cpu,1925-7.html
> 
> Sounds like a question for AMD. The Phenoms seem to be
> pretty good
> except for the extra 10-11w of power draw at idle which is
> disappointing.
> 
> -Dave

Thanks - that definitely answered my question. And I'm using b3 stepping.