On Sun, 12 Jun 2016 11:51:50 -0400, Mr.E wrote:

I need to replace a fan on the 13n2950 cpu cooler but I have no source
of the fan specs as to a replacement. It does use onboard fan speed
modulation so the current needs to be close.
Thanks

You can buy the fan and heat sink assembly from many vendors:
https://www.google.com/#q=13n2950
https://www.google.com/#q=13n2951
I'll assume that the label on the fan has no useful info or is
missing. You can measure the case size with a ruler. The fan power
is probably 12V and you can measure the maximum current by just
applying 12V to the red and black wires and measuring the current with
an ammeter, leaving the white wire unconnected. However, there's the
problem of whether the third wire supplies tachometer feedback (i.e.
speed info), or some kind of pulse width sensing. You should be able
to determine that with an oscilloscope. Then, you get to sift through
data sheets trying to find a suitable match. Unless you need a fair
quantity of fans, I suspect that you will find it easier and cheaper
to just buy the assembly:
http://www.ebay.com/sch/i.html?_nkw=13n2950
http://www.ebay.com/sch/i.html?_nkw=13n2951
https://www.amazon.com/Genuine-IBM-Thinkcenter-Desktop-Heatsink/dp/B00MFW7H5C


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Jeff Liebermann
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Santa Cruz CA 95060 http://802.11junk.com
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