From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id EACF8139BC6 for ; Thu, 17 Sep 2015 13:36:54 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 1BF18E08D9; Thu, 17 Sep 2015 13:36:42 +0000 (UTC) Received: from mail-wi0-f172.google.com (mail-wi0-f172.google.com [209.85.212.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id D9E27E08D1 for ; Thu, 17 Sep 2015 13:36:40 +0000 (UTC) Received: by wicfx3 with SMTP id fx3so27706723wic.0 for ; Thu, 17 Sep 2015 06:36:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-type:content-transfer-encoding; bh=H0Y16atG7O8iyCjmRGYorpBl+EAdJfQ+CwYdTWW2Hco=; b=VX0zcu0Y+i4YDmx3jGHgSRW7nSk/XymyDNoMiMWBoqyE+ef1k7qo7dF3OEvBNq8LqT nCGal+8oK2xRjJ7QCijRoo6r5Dd167Rr43l/i9T1tM2n7fuj6JB1OtKFVJB+uKQCErAa 4aKkrjCBUbFNuyNk928dqdXHxXZwue07e08RHsnX5qTgNqUOYWeNlRMgYINwDpsilj20 oCB6G/Jffk6RyjSfJTDEp5ciDWoyj8aZ47xKq+9Uty/NDLltXFwvfbUFovmSq2uY8sNl CB/N4i9Md2xBV+xUr8Pyco3g0iMVQJQZXoAs+t+hpyaGG0aLzZLRbjEpSw1HRYfuOtX8 cQqA== X-Received: by 10.180.39.175 with SMTP id q15mr27346029wik.73.1442496999421; Thu, 17 Sep 2015 06:36:39 -0700 (PDT) Received: from [172.20.0.41] (105-237-195-3.access.mtnbusiness.co.za. [105.237.195.3]) by smtp.googlemail.com with ESMTPSA id kb5sm3499604wjc.17.2015.09.17.06.36.37 for (version=TLSv1/SSLv3 cipher=OTHER); Thu, 17 Sep 2015 06:36:38 -0700 (PDT) Subject: Re: [gentoo-user] Re: new machine : case + power To: gentoo-user@lists.gentoo.org References: <20150917030432.GE1080@ca.inter.net> From: Alan McKinnon Message-ID: <55FAC1D2.4040706@gmail.com> Date: Thu, 17 Sep 2015 15:36:18 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Archives-Salt: fa30e264-a5f8-4d10-a24a-e20b002a8b59 X-Archives-Hash: 0f7a3fde5d60e12f2bfb5a1c8a9c3fb1 On 17/09/2015 15:26, james wrote: >> With that GPU, you don't need more than 400W. And the amps on the 12V >> > rail are also not important, as that only comes into play with >> > higher-end GPUs. Other features can still be important though, like >> > protection against surges and such (think lightning strikes that can >> > potentially damage your PC, or some PSU malfunction that could do the same.) > > True, but you are not considering transient voltage swings. If your rig > draws 350 W and you have a 400 W PS, you will get spikes and draw-downs > on the voltage during transient period of peak usage. This will kill a PS > over time, faster that if the 350W rig is running off a 500W supply. > Lots of quality capacitors in the PS minimize these effects. If the PS > is rated as extremely efficient (compared to other PS) then it has > better quality components inside the PS (they react faster to transients). I have yet to see a computer that draws 350W sustained :-) Spikes of brief duration yes, sustained no.[1] But now I'm being pedantic right after you tried so hard not to be. [1] Anyone who wants to know just how much power 350W really is, consider that your electric kettle is about 1000W and can boil 1.7l of cold water in 2 minutes. I know [CG]PUs get hot, but they don't get *that* hot. -- Alan McKinnon alan.mckinnon@gmail.com