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View Full Version : Question: How to keep a fan running when my computer is off?

VinnyTAMU
05-08-09, 04:25 PM
So as the title states I am looking for a way to keep a single fan running in my system after I have powered down the system. Is this possible and if so what do I need to do to achieve this?

FYI the PSU I have in the system is an Antec earthwatts EA430 430W
Neuromancer
05-08-09, 04:53 PM
Convert an old ac adapter to power the fan
deadlysyn
05-09-09, 02:48 AM
Convert an old ac adapter to power the fan

This would be the only way I can think of also. You would have to have a way to shut down your mobo and keep the psu running, which could probably be done with relays. But I would think that method would come with several risks of damaged parts.
neonblingbling
05-09-09, 04:57 AM
What are you trying to cool after the computer is off? I would think nothing would get hotter after everything is turned off.
VinnyTAMU
05-09-09, 11:58 AM
Convert an old ac adapter to power the fan

Yea I do have one that I can use, looks like that is the best way.

What are you trying to cool after the computer is off? I would think nothing would get hotter after everything is turned off.

This will installed in an Thermaltake Armor case which houses my server and mini-itx embedded pfsense board. The server will be turned off during the day while the embedded pfsense board will be running 24x7. It does not produce alot of heat, but confined to a case that has no airflow I don't want to take any chances.
zbo
05-09-09, 01:17 PM
Would you not be able to find 12v somewhere on the ITX machine to use to power the fan?
VinnyTAMU
05-09-09, 01:45 PM
Would you not be able to find 12v somewhere on the ITX machine to use to power the fan?

Not that I can see. This is the board that will be running 24x7 and that I want to cool.

**LINK** (http://www.mini-box.com/Alix-2B-Board-3-LAN-3-MINI-PCI_4?sc=8&category=754)
zbo
05-09-09, 01:47 PM
you could always use the USB to gives fan 5v.
VinnyTAMU
05-09-09, 02:11 PM
you could always use the USB to gives fan 5v.

Hey that is a great idea! Thanks!

Looks like I will be giving this *Link* (http://www.cubeowner.com/forums/index.php?showtopic=9632) a try.
Jolly-Swagman
05-09-09, 02:16 PM
One thought to keep in mind some fans dont like being under 7volts amd wont spin up @ 5volts
VinnyTAMU
05-09-09, 02:18 PM
One thought to keep in mind some fans dont like being under 7volts amd wont spin up @ 5volts

Yea I was thinking that might be a problem. I have several 120mm and 80mm fans I can try. Surely out of the three different types that I have one is bout to operate at 5v.
hainer36
05-09-09, 02:59 PM
you could also go with something like this
http://www.coolerguys.com/840556087977.html

i have this one (http://www.coolerguys.com/840556029977.html) and a zalman 3pin (2x12v+2x7v) adapter hooked up to it with 2 yate loons cooling my HT receiver when its on, as it is sandwiched where not alot of heat could escape.
Ach3r0n
05-09-09, 09:55 PM
I just saw a fan the other day that comes with an AC adapter so you can power it with or without the PC. I can't remember where I saw it though. :x ... but they do make one.
meionm
05-10-09, 07:54 AM
Just convert adjustable ac adapter, then you can adjust voltage between 5v and 12v. I used one for cooling my hard drives when I was running nas
deadlysyn
05-11-09, 07:49 PM
I don't think usb is enough on the amperage side to power a fan. I think the ac\dc adapter is going to be the safest route.