From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: problem with cpu eating too much power, prize given if solved Date: Wed, 30 Jun 2004 21:35:03 +0200 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <20040630193502.GB12631@elf.ucw.cz> References: <20040624153513.GB19545@rap.rap.dk> <20040628204008.GK698@openzaurus.ucw.cz> <20040629221111.GB25464@elf.ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Michael Frank Cc: keld-6PR53cSIHaE@public.gmane.org, acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi! > Please refer to http://acpi.sourceforge.net/documentation/sleep.html > and ACPI spec 2.0a around Page 216 > > "Sleep States > S1 - "Stopgrant" > Power to cpu is maintained, but no instructions are executed. > The CPU halts itself and may shut down many of its internal > components. In Microsoft Windows, the "Standby" command > is associated with this state by default. > " > > If you look at the original post, S1 "Stopgrant" costs 5W on his celeron. > It takes a lot > more on many 90nm chips. I read in the Centrino datasheet that it can draw > 15W > stopgrant at _maximum_ vcore!!!. The maximum possible power consumption > is only 25W!. > Now, that is life with modern CMOS, leakage is most of the power > consumption.... > I think it will improve but 1:3 is the best you can expect for multi GHZ > CPU's. > > The transmeta i am typing takes only 0.5W in Stopgrant but is performace > is much less at > "full power" of 5W/600MHz. Its standby to full power ration is 1:10, vs 2:3 > for P4EE's... > > So again, which (mainboard/notebook) HW does depower the CPU and keeps the > rest running ? > As to ACPI there should be a S2.5 state, or a S3 extension to power down > the CPU and run the rest... Does not that look close to S2? > So, I stick to the validity of my original post :) Okay, looks like I was wrong. Pavel -- People were complaining that M$ turns users into beta-testers... ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl! ------------------------------------------------------- This SF.Net email sponsored by Black Hat Briefings & Training. Attend Black Hat Briefings & Training, Las Vegas July 24-29 - digital self defense, top technical experts, no vendor pitches, unmatched networking opportunities. Visit www.blackhat.com