On 12/25/2016 09:45 PM, Luigi Rosa wrote: <<>>> The other kind of server is sold both in "tower" and rack form factor; > they are bigger the airflow is forced by bigger fans that can turn to a > lower speed to exchange the heat. > > If the noise is produced by the rack fans, use, as someone else > suggested, variable speed fans regulated by a temperature sensor. > > In essence, you can greatly lower the noise "by design", but if you > already have the equipment it can be too late. >}} not totally true. there is a very easy way to change fix to variable speed. BTDT. -- The important thing is not to stop questioning. - Albert Einstein CentOS GNU/Linux 6.8 KDE 4.3.4 peace out. tc,hago. g . =+Tired of having your microsoft os hacked? Change to Linux os, used by microsoft hackers. =+If Bill Gates got a dime for every time Windows crashes... ...oh, wait. He does. THAT explains it! =+in a world with out fences, who needs gates. =+ -- The important thing is not to stop questioning. - Albert Einstein CentOS GNU/Linux 6.8 KDE 4.3.4 peace out. tc,hago. g . =+Tired of having your microsoft os hacked? Change to Linux os, used by microsoft hackers. =+If Bill Gates got a dime for every time Windows crashes... ...oh, wait. He does. THAT explains it! =+in a world with out fences, who needs gates. =+=
On 12/25/2016 10:22 PM, geo.inbox.ignored wrote:> there is a very easy way to change fix to variable speed. BTDT.in a rack server with arrays of fans in hotswap sliders inside the server that plug directly into the power distribution board? example: https://photos.smugmug.com/By-Date/2012/2012-02-09/i-vKQf8K5/1/X2/IMG_0322-X2.jpg pray tell how thats 'very easy' ? that particular server has 14 internal fans (there's another row of 7 beneath the ones visible) -- john r pierce, recycling bits in santa cruz
On 12/26/2016 12:31 AM, John R Pierce wrote:> On 12/25/2016 10:22 PM, geo.inbox.ignored wrote: >> there is a very easy way to change fix to variable speed. BTDT. > > in a rack server with arrays of fans in hotswap sliders inside the > server that plug directly into the power distribution board? > > example: > https://photos.smugmug.com/By-Date/2012/2012-02-09/i-vKQf8K5/1/X2/IMG_0322-X2.jpg >}} fine looking box. oem, model? would like above to pull manuals. awaict, 6 fans, 4 power style connectors = power+tack, or sata drive, or 3 volt supply connectors.> pray tell how thats 'very easy' ? that particular server has 14 > internal fans (there's another row of 7 beneath the ones visible) >}} note:: easy male to female fan power 'dongle' with temp to speed controller. insert between fan power cable and fan power socket. do not claim to be 'it'. nor do i came dcs, dce. do claim; design ic control systems - 1969, build, maintain, service, s100 micro computers - 1974 so, yes, easy... ;=) if you run a web search for such a 'dongle' available, you should find plenty. rotron.com is down, can not supply url. -- The important thing is not to stop questioning. - Albert Einstein CentOS GNU/Linux 6.8 KDE 4.3.4 peace out. tc,hago. g . =+Tired of having your microsoft os hacked? Change to Linux os, used by microsoft hackers. =+If Bill Gates got a dime for every time Windows crashes... ...oh, wait. He does. THAT explains it! =+in a world with out fences, who needs gates. =+=
geo.inbox.ignored wrote on 26/12/2016 07:22:> not totally true. > > there is a very easy way to change fix to variable speed. BTDT.1U and 2U HP/Dell servers use variable speed fans, you hear them at full speed when you power the server on. The problem is that the noise of an "idle" 1U or 2U server is far greater than the noise of a 5U server for three main reasons. 1. The small servers have less airflow space, so if you want to move (say) 1 cubic meter of air per hour you have less space, so you must increase the speed of the air 2. The fans are smaller, so the blades must turn faster to move the same amount of air 3, Small servers have smaller dissipating area/volume, so to exchange the same amount of heat you must increase the airflow speed. -- Ciao, luigi / +--[Luigi Rosa]-- \ Organic chemistry is the chemistry of carbon compounds. Biochemistry is the study of carbon compounds that crawl. --Mike Adams
On Mon, December 26, 2016 12:31 am, John R Pierce wrote:> On 12/25/2016 10:22 PM, geo.inbox.ignored wrote: >> there is a very easy way to change fix to variable speed. BTDT. > > in a rack server with arrays of fans in hotswap sliders inside the > server that plug directly into the power distribution board? > > example: > https://photos.smugmug.com/By-Date/2012/2012-02-09/i-vKQf8K5/1/X2/IMG_0322-X2.jpg > > > pray tell how thats 'very easy' ? that particular server has 14 > internal fans (there's another row of 7 beneath the ones visible) >The worst part in the approach "make rackmount machines quieter" is: these machines are designed with high density of power per physical space and efficient cooling in mind (as computers do not produce mechanical work, hence virtually all consumed power goes into heat). Noise level is never considered as a goal. So, attempting to make rackmount machine quieter is counter productive. Just my $0.02 Valeri> > -- > john r pierce, recycling bits in santa cruz > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos >++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++
On Mon, December 26, 2016 12:22 am, geo.inbox.ignored wrote:> > > On 12/25/2016 09:45 PM, Luigi Rosa wrote: > <<>> > >> The other kind of server is sold both in "tower" and rack form factor;I personally do not consider these tower machines put sideways rackmount servers. Such tower machine is usually not designed to works in the server room (where cost per square foot of floor space per Month is consideration), a bunch of machines like that can be replaced by single real rackmount server, the last usually would be much more robust and durable as they are designed to work more stressed. Of course, server room full of tower machines would be quieter, but that one I would rather describe as room full of servers instead of server room (should use the word desktops or workstations not servers for the former). I should have added "rant" tags... I have mild excuse though: I do have my share of trouble from these put on the side towers (chosen by somebody else) in my server room. Valeri>> they are bigger the airflow is forced by bigger fans that can turn to a >> lower speed to exchange the heat. >> >> If the noise is produced by the rack fans, use, as someone else >> suggested, variable speed fans regulated by a temperature sensor. >> >> In essence, you can greatly lower the noise "by design", but if you >> already have the equipment it can be too late. >> > }} > > not totally true. > > there is a very easy way to change fix to variable speed. BTDT. > > > -- > > The important thing is not to stop questioning. > - Albert Einstein > > > CentOS GNU/Linux 6.8 > KDE 4.3.4 > > peace out. > > tc,hago. > > g > . > > =+> Tired of having your microsoft os hacked? > Change to Linux os, used by microsoft hackers. > =+> If Bill Gates got a dime for every time Windows crashes... > ...oh, wait. He does. THAT explains it! > =+> in a world with out fences, who needs gates. > =+> > -- > > The important thing is not to stop questioning. > - Albert Einstein > > > CentOS GNU/Linux 6.8 > KDE 4.3.4 > > peace out. > > tc,hago. > > g > . > > =+> Tired of having your microsoft os hacked? > Change to Linux os, used by microsoft hackers. > =+> If Bill Gates got a dime for every time Windows crashes... > ...oh, wait. He does. THAT explains it! > =+> in a world with out fences, who needs gates. > =+> _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos >++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++