Help With my Zalman 9700

amk21

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Nov 29, 2007
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Long time reader first time poster. I recently purchased the http://www.newegg.com/Product/Product.aspx?Item=N82E16835118020 for my AMD Opteron 185, not knowing that it required a 4 pin power connector, my motherboard only supports a three pin connector. So my question is should i return my Heat sink and purchase a http://www.newegg.com/Product/Product.aspx?Item=N82E16835118019 which i believe that it is the same besides it comes with a 3 pin connector. And finally is there a 4 pin to three pin converter that i would be able to purchase. I looked on newegg and other various sites for such a converter, but i could not locate one. Thanks for any input or opinions you may have to share.
 

rgeist554

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Oct 15, 2007
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I'd wait for a second opinion, but I believe you can still use it on a 3 pin motherboard. I think the 4th pin is to allow you to control the fan speed. Like I said though, I'm not 100% this is true, but I'll do some research and check it out.
 

amk21

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I found this article that that i believe backs up you presumption.http://support.intel.com/support/motherboards/desktop/sb/CS-012074.htm
It appears that a 4 pin heat sink and fan is backwards compatible with 3 pin motherboards. I will lose the ability to control my fan speed via a gui in windows, but i can still control it in the bios. Not sure about this information but it seems to make some sense.
 

weegeebored

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Well I made a noob mistake and purchased the Zalman 9700 LED version for a brand new build and I have the same problem as amk21. Well, actually worse as I already installed the Zalman. (I said it was a noob mistake.) I can tell you that on a Gigabyte GA-P35-DS3R connecting the 3-pin Zalman connector to the MB's 4-pin does not work as the cooler fan does not spin. The cooler is not defective as I've hooked it up to a 3-pin connector on the board and it works fine. The system starts up but after a couple of seconds it will shut down. I'm assuming that the default "Smart Fan" bios setting checks to see if there is indeed a CPU fan connected to the 4-pin and will shut down if it doesn't find one. Under my current situation, I can't get in to the bios to turn off the Smart Fan feature.

I can think of two possible solutions but neither of them thrill me too much. One, I could remove the Zalman, connect the stock Intel heatsink/fan (4-pin connector), boot into the bios, and then turn off the Smart Fan feature. Then, I could (try to) reconnect the Zalman and hope that the new bios setting will let the Zalman fan spin. But, wouldn't that leave me in a situation that if the Zalman fails the MB wouldn't shut the system down and I would fry the CPU?

The second solution is a variation of the first. Just connect the stock cooler without uninstalling/disconnecting the Zalman and hope that this allows me to boot into the bios and change the settings as above. I would still have the same potential problem, though.

I know that there are a bunch of experienced people here. :) Can someone think of another alternative? BTW, emails to Zalman have gotten me zero replies.
 

cnumartyr

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The fourth lead is for Pulse Width Modulation control of the fan. I've had a 3-lead fan plugged into my 4 pin header, it's not a big deal.

Look for voltage control of the CPU fan rather than PWM control. Not sure where to look on your board.
 

weegeebored

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Well, I chose my 2nd option and and just connected the stock HSF to the 4-pin CPU fan header, and also connected the Zalman to a 3-pin fan header so that the CPU would be cooled. That did indeed allow me to get into the bios, and from there I disabled the Smart Fan feature. From all of the things that I have read, including rgeist554's reply here and the Intel support page, connecting the Zalman 3-pin connector to the 4-pin header should have worked, albeit with the fan at a constant full speed. That wasn't an issue because of the Fan Mate speed controller included with the 9700. However...

...the 9700's fan still won't spin up when plugged into the 4-pin header. The Gigabyte board also has a 2nd 4-pin fan header, so for snicks and giggles I tried connecting the 9700 to that one with the same no-go result. So it looks like the only way to get the 9700 LED model to work on the GA-P35-DS3R is via a 3-pin header.

I hope this helps people with a similar problem, but if someone has an alternative that would be great.