A8V Deluxe - fan connections

[Jerome]

I just set up an A8V Deluxe board and bought some new case fans that can
connect to the motherboard connectors, but I am a bit confused. The fans
come with the little connectors for the motherboard and the larger
connectors for the power supply plugs.

Do I use both?

Or do the little connectors provide power to the fans and I can ignore the
larger connectors?

I tried using just the little connectors but the fans didn't run - maybe
the machine wasn't warm enough to cause them to be needed?

The booklet for the mobo just says there are connections, and not how to
use them and since these type of fans are new to me (Antec 80mms) I'm not
sure the correct way to set them up. Right now I am powering them from the
power supply and have them connected to the mobo connectors, and the fans
run all the time.

 

[Paul]

I just set up an A8V Deluxe board and bought some new case fans that can
connect to the motherboard connectors, but I am a bit confused. The fans
come with the little connectors for the motherboard and the larger
connectors for the power supply plugs.

Do I use both?

Or do the little connectors provide power to the fans and I can ignore the
larger connectors?

I tried using just the little connectors but the fans didn't run - maybe
the machine wasn't warm enough to cause them to be needed?

The booklet for the mobo just says there are connections, and not how to
use them and since these type of fans are new to me (Antec 80mms) I'm not
sure the correct way to set them up. Right now I am powering them from the
power supply and have them connected to the mobo connectors, and the fans
run all the time.

Rather than explain all the possible combinations of cables that
come with fans, I'll take a guess that the three pin connector
has a single yellow wire on it. The other connector is for power
and has the Molex 1x4 disk drive connector(s).

When you connect the fan's Molex connector to a disk drive
power connector from the ATX PSU, the fan will get power to spin.
(It uses the +12V and GND, of the possible +12V,GND,GND,+5V pins on
the Molex.)

If you decide to connect the three pin fan connector with the
single yellow wire on it, to a motherboard header, that
carries the tachometer (RPM) signal to the motherboard.
Assuming the motherboard picks up that signal and connects
it to monitor hardware, you'll be able to read the RPMs
of the fan in software.

If the above description matches what you've got, then connect
both of them. If the three pin fan connector has some other wire
configuration, describe it in more detail.

The fans should run all the time, as they are connected
right to the +12V and GND on the Molex connector.

Some of the available case fans out there now, have a
thermal sensor. That allows that type of fan to adjust
its own speed, according to the computer case air temperature.
I see on the Antec web site, that their "SmartCool" fans
do something like that. They also make the older fixed
speed fans as well.

There are also some fans that come with a small adjustment
pot on the end of a cable. You can dial those to the
desired fixed speed to reduce the noise. I got some Enermax
fans like that, but they smell so bad, I cannot use them.

HTH,
Paul

 

[Jerome]

Rather than explain all the possible combinations of cables that
come with fans, I'll take a guess that the three pin connector
has a single yellow wire on it. The other connector is for power
and has the Molex 1x4 disk drive connector(s).

When you connect the fan's Molex connector to a disk drive
power connector from the ATX PSU, the fan will get power to spin.
(It uses the +12V and GND, of the possible +12V,GND,GND,+5V pins on
the Molex.)

If you decide to connect the three pin fan connector with the
single yellow wire on it, to a motherboard header, that
carries the tachometer (RPM) signal to the motherboard.
Assuming the motherboard picks up that signal and connects
it to monitor hardware, you'll be able to read the RPMs
of the fan in software.

If the above description matches what you've got, then connect
both of them. If the three pin fan connector has some other wire
configuration, describe it in more detail.

The fans should run all the time, as they are connected
right to the +12V and GND on the Molex connector.

Some of the available case fans out there now, have a
thermal sensor. That allows that type of fan to adjust
its own speed, according to the computer case air temperature.
I see on the Antec web site, that their "SmartCool" fans
do something like that. They also make the older fixed
speed fans as well.

There are also some fans that come with a small adjustment
pot on the end of a cable. You can dial those to the
desired fixed speed to reduce the noise. I got some Enermax
fans like that, but they smell so bad, I cannot use them.

HTH,
Paul

Thanks - it helped. My fans are Antec SmartCool fans with the Molex and
small extra plug. Look slike I have them connected right and now I just
have to find a way to control the fan speed from Linux.

I wish there was a way to have them idle until needed but I don't see any
way to do that except to look into some user-land utility so now I know
they're connected correctly I can look into what to do next.

 

[Paul]

Thanks - it helped. My fans are Antec SmartCool fans with the Molex and
small extra plug. Look slike I have them connected right and now I just
have to find a way to control the fan speed from Linux.

I wish there was a way to have them idle until needed but I don't see any
way to do that except to look into some user-land utility so now I know
they're connected correctly I can look into what to do next.

There are many ways to control fans, and as with all things retail,
it is not that easy to kludge together something to give you a
degree of control.

Your SmartCool fan is designed such that you cannot easily control
it from software. If it uses a three wire cable with three pin
connector, there are more options for controlling a fan with a
regular three pin connector (I call that a "dumb" fan). Here is
an example of a device I use to crank down fixed speed fans,
to a more silent level. This doesn't give you a different speed
as the temperature changes. A dumb fan plus one of these is what
I like.

http://www.silentpcreview.com/files/images/fan_controller/fanmate1-2.jpg

I have an Antec power supply that has some "fan only" molex disk
drive connectors. The voltage on the "fan only" cable is determined
by the temp inside the power supply, so the fans running off those
cables will speed up if the case air gets hotter. Slapping
an Antec SmartCool onto one of those "fan only" connectors
would give you a fan that was so slow as to be useless. A
dumb fan connected to one of those would still be spinning.

If you wish a "zero cost" solution, you can take the SmartCool
fan, and rewire the connector, to connect the +12 and GND of the
fan, to the +12 and +5V pins on the Molex end. Since there are only
two pins installed in the Antec connector, you would be moving
one of the pins into a different hole. If you were to do this,
you can no longer hook up the tachometer signal to the motherboard
(the ground reference on the fan is now lifted to +5V, which is
no good for making the RPM signal work properly). While
this will work, I don't use this technique on my gear.

Original Position Modded Position (puts 7V across fan)
(By moving black wire and pin to the
+5V position on the connector.)

x x GND +12 +5 x x +12
Black Red Black Red

I have also used silicon diodes as voltage dropping devices.
A silicon diode drops roughly 0.7V when a decent current
flows through it, and by placing from one to seven diodes
in a row, you can drop 0.7V to 4.9V of applied voltage.
To do this, you cut the red +12V wire between the fan and
Molex, and install the diodes. The "band" around one end
of the diode (cathode) goes away from the Molex end. The
more diodes, the slower the fan goes, and the tachometer
signal on the separate three pin, is still valid when
doing this. (Because GND is still GND.) Diodes of type
1N4001 through 1N4007 can be used for a job like this,
and my local electronics store sells them in bags of 25
devices for a few dollars. (Some suppliers charge much
higher prices, making this too expensive as a solution.
I would not buy the diodes at Radio Shack, for example.)

band band
Molex | |
v v
x x GND +12 ------- diode --- diode ------------- the
| fan
+-------- original_black_GND_wire_untouched--- end

http://www.diodes.com/tracker/pdftr...om/products/catalog/search.php&ds=ds28002.pdf

For the ultimate control, some dumb fans plus a
T-Balancer gives programmable control.

http://www.tomshardware.com/2004/11/22/mcubed/index.html
http://www.mcubed-tech.com/eng/produkte.htm

HTH,
Paul