From owner-freebsd-questions@FreeBSD.ORG Sun Feb 6 10:43:53 2005 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E2BEF16A4CE for ; Sun, 6 Feb 2005 10:43:53 +0000 (GMT) Received: from mail.freebsd-corp-net-guide.com (mail.freebsd-corp-net-guide.com [65.75.192.90]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5670843D3F for ; Sun, 6 Feb 2005 10:43:53 +0000 (GMT) (envelope-from tedm@toybox.placo.com) Received: from tedwin2k (nat-rtr.freebsd-corp-net-guide.com [65.75.197.130]) j16Ahsj98578; Sun, 6 Feb 2005 02:43:54 -0800 (PST) (envelope-from tedm@toybox.placo.com) From: "Ted Mittelstaedt" To: "Peterhin" , Date: Sun, 6 Feb 2005 02:43:50 -0800 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.6604 (9.0.2911.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441 In-Reply-To: <200502051745.25937.hindrich@worldchat.com> Importance: Normal Subject: RE: Leaving a Computer Running ? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 Feb 2005 10:43:54 -0000 > -----Original Message----- > From: owner-freebsd-questions@freebsd.org > [mailto:owner-freebsd-questions@freebsd.org]On Behalf Of Peterhin > Sent: Saturday, February 05, 2005 2:45 PM > To: freebsd-questions@freebsd.org > Subject: Leaving a Computer Running ? > > > > Is it better to leave a computer (a stand alone) running > continuously or > is it OK to shut it down at the end of the day.? It is better to shut it down at the end of the day, unless it will have periods of time (such as weeks) where it will need to be left on continuously. > I remember years ago someone mentioned that it is better for the > circuitry to leave it running. No. The problem is in disk drives and power supply and CPU fans. Fans in computers today aren't what they used to be. Most of them have very bad or nonexistent dust shields and so the longer they run the more dust gets into their bearings, whereupon the bearings eventually get clogged and the fan stops turning. Periodically taking apart the PC and blowing it out with compressed air does not lengthen the life of the fans, although it is a good idea to do as it helps the machine run cooler (as long as the fan is still working) Once the fan stops the electronics overheats and becomes unreliable. Disk drives are particularly suceptible to damage from overheating and will fail years before a circuit board in an overheat situation. In a clean room or positive pressure network room, where there is an extremely low level of dust, off-the-shelf computer fans will last many years longer than fans in a typical home PC. So for the daily driver PC's you want to turn them off to lengthen the life of the fans. For PC's left on for long periods, they have a different problem because disk drives that spin at full speed continuiously (as server drives do, servers have power saving disabled on their drives of course for obvious reasons) the disk will eventually overheat in just about all the garden-variety case designs. (you can fix this yourself of course, by adding more fans to the cases) Once the drive overheats the lubrication migrates out of the bearings and if the drive is turned off for more than 6-8 hours, it cools down enough to the point that the drive will never spin up again. Ted