From owner-freebsd-questions@FreeBSD.ORG Mon Jun 23 19:18:21 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 BA217106566B for ; Mon, 23 Jun 2008 19:18:21 +0000 (UTC) (envelope-from josh.carroll@gmail.com) Received: from wf-out-1314.google.com (wf-out-1314.google.com [209.85.200.175]) by mx1.freebsd.org (Postfix) with ESMTP id 86EC38FC19 for ; Mon, 23 Jun 2008 19:18:21 +0000 (UTC) (envelope-from josh.carroll@gmail.com) Received: by wf-out-1314.google.com with SMTP id 24so2093106wfg.7 for ; Mon, 23 Jun 2008 12:18:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:reply-to :to:subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references; bh=8FjrySU4xoWQOor3ErdSPif+AYdsDb97+gIyWwwGOoo=; b=rc9nGN1VgNjX+MByjr8MIROEfE1RFuy5BnBrz25PcaoiVRwnWd5oHM1wq+ZDeOzHhw J1lqDcAVes75NCq9z4Qn+tUEWqnbJ6t9QB0No3JRMKCHax2iRUJ3l3vpOdA0aDioqa5M 5NDebeme7MQL4RfUmKyC3/vgCATH+4T1O21BQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:reply-to:to:subject:cc:in-reply-to :mime-version:content-type:content-transfer-encoding :content-disposition:references; b=TEo+sQT1kEpuMqixJ6JNC/ah2lW0tBkRhQfM69nzayQYyn3dTEAQNm3YXJ/Y8Bv5/F VAxzftgB1CCOzXiLdanYl1jELA+5CKcc2NJ8pYT1PHk7I4YMgaqY20orbmzc0NURs7cS 1SVr2cR9OueSxTBJWSjlGkYv3sHBPZhAPZSVM= Received: by 10.142.89.13 with SMTP id m13mr4344459wfb.338.1214248700934; Mon, 23 Jun 2008 12:18:20 -0700 (PDT) Received: by 10.150.140.14 with HTTP; Mon, 23 Jun 2008 12:18:20 -0700 (PDT) Message-ID: <8cb6106e0806231218jcbdffa8jec894b7fb31290c4@mail.gmail.com> Date: Mon, 23 Jun 2008 15:18:20 -0400 From: "Josh Carroll" To: hartzell@alerce.com In-Reply-To: <18527.62508.451095.415706@almost.alerce.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <18527.62508.451095.415706@almost.alerce.com> Cc: freebsd-questions@freebsd.org Subject: Re: CPU temp's on core 2 duo, should they be significantly different? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: josh.carroll@gmail.com List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Jun 2008 19:18:21 -0000 > I've noticed that cpu.0 is consistently hotter than cpu.1, even on an > unloaded machine. Is that because that core's doing housekeeping work > whilst the other is truly idle? > > dev.cpu.0.temperature: 44 > dev.cpu.1.temperature: 29 I notice some differences on my quad-core (Q6600) CPU, too: dev.cpu.0.temperature: 35 dev.cpu.1.temperature: 34 dev.cpu.2.temperature: 27 dev.cpu.3.temperature: 30 The differences also stay around the same when I yes > /dev/null 4 times to load up each core: dev.cpu.0.temperature: 47 dev.cpu.1.temperature: 45 dev.cpu.2.temperature: 38 dev.cpu.3.temperature: 42 The discrepancy isn't as much as in your case, though. 15 C is pretty significant. It could be that either your heat spreader or heat sink are concave or convex causing one of the cores to get hotter. On my dual-core box, here are the idle temps: dev.cpu.0.temperature: 33 dev.cpu.1.temperature: 31 and under load: dev.cpu.0.temperature: 48 dev.cpu.1.temperature: 46 I'd recommend taking the heat sink off and seeing how the thermal grease is spread on the CPU's head spreader and on the heatsink itself. If it looks lopsided or extremely thick on one side of the CPU package or extremely thin (to the point where you can still see the sheen of the heatsink or heat spreader), then re-mount the heatsink and try to make sure it's evenly distributing the pressure down on the CPU package. Josh