Computer Hope

Hardware => Hardware => Topic started by: zeroburn on January 21, 2012, 11:14:34 AM

Title: Too Many Computer Fans
Post by: zeroburn on January 21, 2012, 11:14:34 AM
I am currently building a beowulf cluster, and i am installing several fans into the case i intend, and i can not plug them into the mother boards of the nodes, and was wondering how much of a good idea it would be to splice one of the power supply outputs and wire the fans directly to the power supply. I have a floppy drive adapter i could splice off of to keep the power supply at it's orriginal state, but are their any suggestions to how i should go about powering 16 fans?
all help appreciated. Thanks
Title: Re: Too Many Computer Fans
Post by: truenorth on January 21, 2012, 11:45:47 AM
16 fans WOW! Why so many? What is going to be causing all the heat? If you really need so much cooling why not consider a "liquid cooler for the CPU? truenorth
Title: Re: Too Many Computer Fans
Post by: zeroburn on January 21, 2012, 12:04:09 PM
it is a beowulf cluster, I happen to be putting all the nodes into a single case. I just want to make sure as *censored* that the thing stays cool. I could just put the air intake to a swamp cooler on the side of the custom case i built for the cluster, but i would rather be normal, or as close to it as i can be. (well, the case is made from a filing cabinet, so, im not sure if it is normal at all)
Title: Re: Too Many Computer Fans
Post by: Salmon Trout on January 21, 2012, 12:37:27 PM
You can power them from a separate power supply; say each one draws 3 Watts; if they are all 12 Volt fans then current draw will be (16 x 3) / 12 = 4 amps so a 12 volt 5 Amp power supply will have some headroom.

Title: Re: Too Many Computer Fans
Post by: zeroburn on January 21, 2012, 12:40:28 PM
if i have the power supply from one of the nodes, the only connection from the power supply being used would be the motherboard connector, the leftover 12v outputs would be enough?
Thanks for the help so far
Title: Re: Too Many Computer Fans
Post by: Salmon Trout on January 21, 2012, 12:47:02 PM
if i have the power supply from one of the nodes, the only connection from the power supply being used would be the motherboard connector, the leftover 12v outputs would be enough?
Thanks for the help so far

Well, if the PSU is beefy enough to supply an extra 50 Watts via the 12 Volt rail you should be all right, but you're the one with access to the figures (total fan consumption, motherboard power draw, PSU specifications). Do the arithmetic.

Title: Re: Too Many Computer Fans
Post by: truenorth on January 21, 2012, 02:02:54 PM
How many computers do you intend to use to make your beowulf? I am sure you have a good idea of what you are doing but given that technical support on here may be limited to a small number of members (certainly not me) doing some research i came across a site for the people that do this. Perhaps it could be a resource for you when you need help.
http://www.beowulf.org/
truenorth
Title: Re: Too Many Computer Fans
Post by: zeroburn on January 21, 2012, 02:06:59 PM
I have been at that site before, although i never got much information on powering the fans from the PSU's themselves. I am however reading one of the e-books from that site explaining more on how to do this.

I plan on having four nodes and the head node all in the same case.
Title: Re: Too Many Computer Fans
Post by: Salmon Trout on January 21, 2012, 02:10:39 PM
You just need a some Molex splitters and if necessary some Molex to fan adapters. If you spread the fan load around 4 PSUs it shouldn't be too bad.

(https://encrypted-tbn2.google.com/images?q=tbn:ANd9GcQQBSrJ-6Vsds_jcnz0JQNumHP1egn8W9iR3Dujo3mGirKFfVUo)(https://encrypted-tbn2.google.com/images?q=tbn:ANd9GcQQJtFzpUZZMhaCDQUMiQsddNSc-QLZ862jIQ8KiJHzKNS5fRBliQ)
Title: Re: Too Many Computer Fans
Post by: rthompson80819 on January 21, 2012, 02:32:11 PM
Sorry, but I have a hard time taking this post seriously.  16 fans, a case made out of a filing cabinet, possible use of a swamp cooler for cooling (probably most of Canadians and Brits have no idea what a swamp cooler is, but it is the last thing anyone would use for cooling a computer).

If it is a serious project, then it needs to be done right right with several real computer cases and standard cooling.
Title: Re: Too Many Computer Fans
Post by: zeroburn on January 21, 2012, 02:49:08 PM
The swamp cooler itself is a joke, however, i do believe i am taking what i am doing seriously.
I have several boards, each equipped with Ethernet, formated BIOS to boot from a networked location, although hard drives are absent
the head node has Ubuntu Server installed, and has the full hard drive configuration unlike the rest of the client nodes
I do not have the room for five cases, and in the future, to be more, to each be hooked into power and running.
I decided the best enclosure for what i am doing is a modified filing cabinet, and some construction to retrofit it to hold the computer hardware necessary.

I am taking a lot of fans into the equation, mostly because i have too many without a purpose and i don't wish to risk ruining the whole computer cluster becoming useless just because of some heat problems.

I would be using something besides a filing cabinet if i had the money to do so, but i have the recourses to just cut apart one into what i need.
Title: Re: Too Many Computer Fans
Post by: rthompson80819 on January 21, 2012, 03:18:11 PM
OK, the swamp cooler thing through me off.  When you say you have several boards, what kind are they and can they be rack mounted, and powered through a heavy duty power supply?  There are power supplies made to power multiple servers.
Title: Re: Too Many Computer Fans
Post by: truenorth on January 21, 2012, 03:20:32 PM
Many of the creators of the Beowulf don't even seem to put the nodes in a case at all--don't know how they create the necessary cooling.truenorth
Title: Re: Too Many Computer Fans
Post by: patio on January 21, 2012, 03:24:13 PM
If you are in fact using a filing cabinet for this rig then why limit yourself to 16 PC fans for cooling ? ?
Title: Re: Too Many Computer Fans
Post by: Kurtiskain on January 22, 2012, 08:04:17 PM
If you are in fact using a filing cabinet for this rig then why limit yourself to 16 PC fans for cooling ? ?

Why not mount a 250mm 240V/110V Fan at each end of the cabinet? one in one out? That will get the air flowing!
Title: Re: Too Many Computer Fans
Post by: Raptor on January 23, 2012, 03:36:29 AM
Got a picture of your project?
Title: Re: Too Many Computer Fans
Post by: patio on January 23, 2012, 07:14:09 AM
Go all out... (http://www.kingersons.com/air-con/9000btuminisplitacseer13aircon.html)
Title: Re: Too Many Computer Fans
Post by: zeroburn on January 23, 2012, 10:56:22 AM
Where would i get these low cost? i have been running on a very limited budget, so therefore, i have only been using what has been available to me to use.
Title: Re: Too Many Computer Fans
Post by: zeroburn on January 23, 2012, 12:18:42 PM
Where would i get the fan? i am on a very limited budget, reason why i am using only what i have available so far.
Title: Re: Too Many Computer Fans
Post by: Salmon Trout on January 23, 2012, 12:32:01 PM
You just duplicated your earlier post.
Title: Re: Too Many Computer Fans
Post by: zeroburn on January 23, 2012, 01:51:24 PM
I sorry, my internet glitched out on that......

Pics are coming soon