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 90D54139BC6 for ; Thu, 17 Sep 2015 13:26:26 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 1DDAA21C083; Thu, 17 Sep 2015 13:26:17 +0000 (UTC) Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 0C9F321C058 for ; Thu, 17 Sep 2015 13:26:16 +0000 (UTC) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1ZcZCW-0007IM-TY for gentoo-user@lists.gentoo.org; Thu, 17 Sep 2015 15:26:14 +0200 Received: from rrcs-71-40-157-251.se.biz.rr.com ([71.40.157.251]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 17 Sep 2015 15:26:12 +0200 Received: from wireless by rrcs-71-40-157-251.se.biz.rr.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 17 Sep 2015 15:26:12 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: gentoo-user@lists.gentoo.org From: james Subject: [gentoo-user] Re: new machine : case + power Date: Thu, 17 Sep 2015 13:26:07 +0000 (UTC) Message-ID: References: <20150917030432.GE1080@ca.inter.net> 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 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: sea.gmane.org User-Agent: Loom/3.14 (http://gmane.org/) X-Loom-IP: 71.40.157.251 (Mozilla/5.0 (X11; Linux x86_64; rv:36.0) Gecko/20100101 Firefox/36.0 SeaMonkey/2.33.1) X-Archives-Salt: 76ad1b7b-e970-4007-8bba-8057995c2b1e X-Archives-Hash: 25a51bbd1254ab269bd3a1ad7e511cd1 Nikos Chantziaras gmail.com> writes: > However, note that PSUs tend to go bad after years of operation. An 8 > years old PSU might start losing power or voltage stability. If you see > random machine resets or hangups, it's usually because the PSU is dying. Very true. However, if you are "handy with electrical wiring", DC voltage analysis, live, is quite simple. Just monitor the voltage outputs, under load with a "multi meter" and see if the voltages sags below the unload rail (dc voltage level). Also the most common failure of PC style PS is the fan and those can be changed for a few bucks. But electronics do age and a good UPS will extend the life of your PS. UPS batteries, typical a 7-10 Amp-hour are cheap to replace ever 2-4 years. Another simple way to do this, and more cool, is the get an amp meter. Just convert the wattage rating of the PS to an amp rating at a given voltage level. Clamp around the power cord running to the PC and you can see the static (non transient) voltage sag if it occurs as the amperage draw increases. If you can find an old analog meter, with a needle on the dial, you can see a transient energy draw by the fast movement of the needle on the dial. Digital meters that can do this, or capture the traces (as in an oscilloscope) are much more expensive, but makes for a fun lab to learn about the operational characteristics of dynamic electrical energy flows. (trying to keep this non-pedantic). > 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). caveat emptor! Size does matter for a long and happy life:: ;-) James