System fan doesn't appear to be compatible with motherboard :(

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My system fan came out of a compaq server.  I don't know too much
about this new machine.
Some basic info I have gathered about it is as follows.

Boot error message:  "Secondary IDE Channel  no 80 conductor cable

Microstar MSI KM3M-V  (MS-7061-01S)


VIA VT8237 chipset

VIA 823 Board drivers downloading now from :

Prompts me to insert "Intel Ultra ATA Storage Driver Disk"

The user manual appears to be at

I'm having two problems right now.  Only Linux sees my 2 DVD drives.
Windows 98 doesn't know they are there. I'm assuming I can get this
fixed with the correct drivers and/or new IDE cable.

The bigger problem is the system fan.  The end of the plug has 5
holes.  The motherboard connector CPUFA1 plug only has 3 thingies. The
CPUFA1 plug appears to be located right next to the memory. My fan's
plug can't reach all the way over there. Even if it could, it has too
many holes.

Am I going to be able to use this fan?????


Re: System fan doesn't appear to be compatible with motherboard :(

dos-man wrote:
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For the fan, somehow I arrived at these numbers. This is a fan for
an ML310 (of which there might be five generations). In one Ebay
advert, the fan was rotated so the hub was visible. Unfortunately,
the smaller part number printing was unclear, but in big letters
the fan was identified as a Nidec Beta V. The link is to the datasheet
for the fan. As you'd expect, there are cabling options for the fan,
so there is no way to know what options are on the cable. To go further
in the search, you'd need to use all the info printed on the hub of
the fan. And even then, the fan could be a custom design only for

Part Number: 287179-001

Cabling options include the following:

Alarm/Tachometer/Thermal Speed Control/PWM Speed Control

Alarm      = likely locked rotor detection = no connection to this pin is needed.
Tachometer = two pulses per rotation, open collector.
              For a chassis fan, monitoring of fan speed is not essential.
              If a CPU fan, then yes, this should be connected.
Thermal    = could use a thermistor. It is more typical in the computer
              industry, to buy a fan with a thermistor inside the fan hub,
              saving on having to do it externally. So maybe this option
              is not on your fan.
PWM        = currently used on Intel retail CPU fans. 25KHz square wave
              driven by motherboard. If open circuit, fan runs at max
              speed, so this does not have to be connected.

+12V/GND   = At a minimum, the fan needs power and ground to run. The
              Nidec datasheet mentions red and black as colors used on their
              two wire cable. But we can't know whether that color choice
              would be used on all possible cable assemblies or not.

The cable assembly may have two ground wires, because I think I see two
black wires. That leaves only three more to figure out. One will be +12V.
One could be PWM. One could be tachometer.

So that doesn't help really, but it is a start. All you really need
to do for a start, is identify the +12V and ground pins. You don't
need to connect the tachometer signal, as it is a chassis fan.

On the motherboard end, the connector has +12V, GND, and tachometer input.
The +12V will offer a limited amount of current, and truly monstrous fans
should not be powered by the fan header. (For example, I have a 12V
at >1 amp fan in my current computer, and to protect the fan header, I
take power for it from a Molex disk drive connector.) If you exceed the
allowed current, either a copper track burns out, or a transistor on
the motherboard gets fried. There is *no* fuse in that path. Some
motherboard manuals have a pinout for the header, and they may
mention the allowed current flow.

    GND +12V Tachometer

      X  X  X


Re: System fan doesn't appear to be compatible with motherboard :(

On Sun, 24 Aug 2008 23:48:36 -0700 (PDT), dos-man

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Win98 should see them as drives, without drivers.  It was
only the really old stuff that needed a driver in Win98.  As
for what to do to get them detected, all I can suggest is
checking jumpers and bios settings.

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The easiest thing would be to just use a different fan.
Sometimes you can peel back the label a little, if the wires
attach to the side the bearing opening is on, and see marks
on the PCB to denote the power lead and ground.  Other times
you have to guess and try momentarily applying power to one
of the colored leads to see if it spins.  FWIW, a different
model of Nidec Beta V here uses red for power, and of course
black for ground.  As for the addt'l positions on the
connector, once you'd desoldered or clipped off the unneeded
wires you can try slicing off the unneeded positions on the
fan's plastic connector block with an X-acto knife or
similar.  Finding out whether one of those addt'l wires is
an RPM lead will be a bit more work, personally I wouldn't
worry about it too much if the fan isn't very worn as Nidecs
tend to be very good quality and unlikely to be an early
failure point unless it has very high RPM.

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Re: System fan doesn't appear to be compatible with motherboard :(

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Sorry, I couldn't get back to this thread in a timely manner due to my
work schedule. At any rate, I followed your advice and put in a new
fan.  I also mounted a smaller fan at the bottom of the tower for
extra cooling.  These Compaq servers have steel towers and I'm told it
gets hot inside there. It's a cool 85F right now.

I got the machine to finally recognize the DVD drives.  Everything is
looking good except for some minor probs with USB flash drives having
two entries in "My Computer".   And the new 1 gig PNY camera cards I
just bought are only showing 570 megs of available storage space on
them.  Those are issues for another day :)


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