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mrmythFlag for United States of America

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HP Media Center M376N Desktop Computer needs CPU Fan

I replaced the fan on this HP Media Center M376N computer that is fairly old.

I replaced the fan that cools the whole computer. I can't find another fan just by looking around. Do you think there is another fan that cools just the CPU?

The BIOS is still telling me that the fan is failing.

Windows XP
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Casey Herman
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The other thing is if it was set up to monitor a fan port that doesn't have a fan connected to it. IE the bios battery is getting old and failing and the computer got unplugged or something and reset the bios.

Casey
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These comments make sense. Do you think there is more than one fan in this machine? I only found the one fan that cools the whole system. Do you think there might be one that is just for the processor, or does CPU fan just refer to the fan on the box?
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There is usually a fan that is mounted on the heatsink which is located on top of the CPU. You can check that one as well to see if your CPU even has a fan mounted on it and if it is working.

but as casedog said there are sometimes plugs on the motherboard that don't have fans attached.
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In the bios temp of CPU says 105 degrees, is that normal?

There are two indicators for fan speed
CPU Fan speed says 0rpm
System fan speed says 1966 Rpm


Can't find where to turn off alert says
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In the bios temp of CPU says 105 degrees, is that normal?

There are two indicators for fan speed
CPU Fan speed says 0rpm
System fan speed says 1966 Rpm


Can't find where to turn off alert says
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Okay so I went and looked at the computer again.

There is the main "System Fan" and it says that it is running at 1966rpm or thereabouts and the BIOS also lists a CPU Fan but that shows a red number 0rpm

I don't see any other fan in there. The main fan goes right into this vent that encloses the big silver grill looking part (I don't know what that's called) that is on the motherboard. It seems so strange that there would be this other connector on the motherboard with no fan, but you are probably right.

I ran a diagnostic tool call Burn It Test on the system and everything seemed to check out. The BIOS then said that the processor was at 105 degrees which seems normal. I checked around on the internet and I saw that 40C is a pretty low temperature for a processor and it's a hot day here.

I don't see a place in the BIOS where I can turn off the alert. It comes on and says you have 5 seconds to press F2 to start the machine. The owner doesn't seem to care too much about that, but I would like to turn it off for him if it's a big deal.

Maybe I should download some software that gives him a CPU temperature indicator so he can be sure it's not overheating.

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The "big silver grill looking part" mentioned above is apparently the heat sink.
apparently from this video picture, you have 2 fans : 1 cpu fan, and 1 power supply fan, as in most PC's :
http://h10025.www1.hp.com/ewfrf/wc/document?docname=bph03429&tmp_task=useCategory&lc=en&dlc=en&cc=us&os=228&product=374755&sw_lang=
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That one has one sitting right on top of the heat sink. This one has a system fan with a plastic piece that directs it straight to the heat sink. There is no fan on the heat sink itself like in the video.
can you post a picture of your (pc) insides ?
>>  bios temp of CPU says 105 degrees   <<   C° or F ?
depending on the cpu model, check here for the max allowed temps : http://www.heatsink-guide.com/content.php?content=faq.shtml

or here :  http://www.hardwaresecrets.com/article/143
also - did you replace the heat paste on the cpu ? that can cause it too
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105 degrees farenheit
I'm pretty sure the Bios is talking about a fan and not heat paste

When I see the computer again I can post a picture, but that won't be until next week.

My plan is to check the BIOS version and upgrade it to the newest version.
how many wires are on the connectors from the fans..
I bet the new fans that you got at least one of them doesnt have the RPM sensor on it and that is why you are getting the failure.

Those kinds of fans should have a red yellow and black at least.

The one you bought probably only has red and black or the pin is in to wrong spot if it is a 4 wire connector.

So the fan is turning fine but since the fan cannot report RPM's back the mother board sees it as a fail.

Casey
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I believe it's just red and black. It also connects to the power which the old fan did not. Why do you think it would report that there are two fans.
that the cpu fan is 0 rpm is normal - since ther e i s none.
did you check the max temp for your cpu ??
how many fans did you replace just one?
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just one. There was only one in there. Unless there is something I'm missing.
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One would think that the cpu fan being 0 rpm would be normal, but why is there no fan? Could it be that it just supports another fan, but how can I turn off the warning?
Ok so here is what I am guessing that happened.. you replaced the fan.  with a two wire fan. You need the three wire fan and you need it to be plugged into the CPU port on the motherboard. Not the system fan port.  The error will stop at that point.  So I would take that fan back and get a 3 wire fan. IT will have the RPM sensor on it and get that plugged into the CPU port.  Good Luck!

Casey
there is no fan on some desktops, instead they install a huge cooling block
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I went back to the computer. Installed some more RAM because the user wanted it. I updated the BIOS to the latest version and now there is no fan error message.
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thanks for the help!