From owner-freebsd-questions@FreeBSD.ORG Tue Oct 7 13:28:34 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id DA0BB10656AA for ; Tue, 7 Oct 2008 13:28:34 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from QMTA01.westchester.pa.mail.comcast.net (qmta01.westchester.pa.mail.comcast.net [76.96.62.16]) by mx1.freebsd.org (Postfix) with ESMTP id 829888FC2B for ; Tue, 7 Oct 2008 13:28:34 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from OMTA02.westchester.pa.mail.comcast.net ([76.96.62.19]) by QMTA01.westchester.pa.mail.comcast.net with comcast id PpDr1a0050QuhwU51pUZil; Tue, 07 Oct 2008 13:28:33 +0000 Received: from koitsu.dyndns.org ([69.181.141.110]) by OMTA02.westchester.pa.mail.comcast.net with comcast id PpUY1a0072P6wsM3NpUYKC; Tue, 07 Oct 2008 13:28:33 +0000 X-Authority-Analysis: v=1.0 c=1 a=dHjZm24hZxkA:10 a=88wOqWrQNcMA:10 a=QycZ5dHgAAAA:8 a=XZDfOCNAwFbK4uAQgtEA:9 a=_J9mGXpy62V8_RY9IN0A:7 a=erBGBHm8cWB2RzrqcCOW1VUPH64A:4 a=EoioJ0NPDVgA:10 a=LY0hPdMaydYA:10 Received: by icarus.home.lan (Postfix, from userid 1000) id 0F245C9419; Tue, 7 Oct 2008 06:28:32 -0700 (PDT) Date: Tue, 7 Oct 2008 06:28:32 -0700 From: Jeremy Chadwick To: Kirk Strauser , FreeBSD Questions ML Message-ID: <20081007132832.GA49914@icarus.home.lan> References: <20081007132517.GA31229@melon.esperance-linux.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20081007132517.GA31229@melon.esperance-linux.co.uk> User-Agent: Mutt/1.5.18 (2008-05-17) Cc: Subject: Re: Coretemp seems to be off quite a bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Oct 2008 13:28:35 -0000 On Tue, Oct 07, 2008 at 02:25:17PM +0100, Frank Shute wrote: > On Mon, Oct 06, 2008 at 09:39:40AM -0500, Kirk Strauser wrote: > > > > I have a Gigabyte motherboard with an Intel ICH-9 chipset, and a > > 3.0GHz Core 2 Duo (E8400). The coretemp sysctls seem to always show > > 50C as the baseline temperature: > > > > $ sysctl dev.cpu | grep temp > > dev.cpu.0.temperature: 50 > > dev.cpu.1.temperature: 50 > > > > This is with a big PSU fan, a good CPU fan, a clean heatsink, and two > > case fans aimed the right direction (front fan pulling cool air in, > > rear fan pushing warm air out). If I reboot and go into the BIOS, I > > get numbers around 42-43C. I know it's kind of hard to compare > > directly, but the coretemp numbers are from a totally idle system with > > powerd scaling it back to 373MHz, so it should be as cool as when > > sitting idle in the BIOS screens. When I work the system hard, like > > running "make -j4 buildworld", I see temperatures up around 63-64C, > > and I'm almost positive that's not right. > > > > Any ideas why coretemp and the BIOS would show such different numbers? > > To add some numbers, I've got an E6550 on a Gigabyte GA-P35-DS3L > (ICH9) and I get: > > $ sysctl dev.cpu | grep temp > dev.cpu.0.temperature: 24 > dev.cpu.1.temperature: 28 > > Ambient room temp: 23°C > > That's running powerd and the machine idle, standard heatsink/fan > combo, 1x12cm case fan. > > Your's might run hotter (higher clock speed? Mine: 2.33GHz) but I > wouldn't expect it to run *so* much hotter. > > I'd expect your numbers to be right if all the ACPI stuff is working. Clarification here is needed: coretemp(4) has nothing to do with ACPI. It gets thermal statistics from the processor by talking *directly* to the processor with specific opcodes, the results returned in specific CPU registers. It does not rely on ACPI. -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |