power source fan speed

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Peter

Hi! I recently noticed that the fan speed of my system's power source is
just 1,200-1,280 RPM. I'm pretty sure that it used to be around 1,500-1,600
RPM. What's normal speed for a power source's fan?

Thanks
 
Peter said:
Hi! I recently noticed that the fan speed of my system's power source is
just 1,200-1,280 RPM. I'm pretty sure that it used to be around 1,500-1,600
RPM. What's normal speed for a power source's fan?

Thanks
Click to expand...
1200 rpm to 1500 is normal speed. Most actual PSU have variable fan speed,
regulated by a temperature sensor. This is probably what happens with your
PSU.
 
Peter typed:
Hi! I recently noticed that the fan speed of my system's power source
is just 1,200-1,280 RPM. I'm pretty sure that it used to be around
1,500-1,600 RPM. What's normal speed for a power source's fan?

Thanks
Click to expand...

Depends on PSU type- some of them have variable fan speed, depending on the
heat inside. How did you measure rpm anyway?
 
I have a program that came with the motherboard. It monitors the temperature
and fan speed.
 
Hi! I recently noticed that the fan speed of my system's power source is
just 1,200-1,280 RPM. I'm pretty sure that it used to be around 1,500-1,600
RPM. What's normal speed for a power source's fan?

Thanks
Click to expand...

That depends on the model of power supply, fan installed, and
with most decent models now having variable speed fan controller,
also on the temp inside.

There is no "normal" speed. For a relatively cool-running
system, 1200 RPM isn't unusual but it _could_ be unusual for your
specific power supply. If you feel that your room temp is the
same, that the system power usage is the same, and airflow is
also the same, then fan speed reduction "could" be a sign of a
pending fan failure. Typically a fan will start making a lot of
noise when that happens, so if it's making noise it'd be good to
replace it asap. Otherwise, replace it if you like but there is
insufficient evidence provided to conclude it is necessary.

If it's a cheap generic sleeve bearing fan, might be good to lube
it now rather than wait and see if it's going to fail.
 
Peter typed:
I have a program that came with the motherboard. It monitors the
temperature and fan speed.
Click to expand...

Measure PSU fan speed? Very few PSU's is so designed that you can actually
measure fan speed of it. Normally you can measure RPM of CPU fan, MOBO fan,
Chipset fan etc..but not PSU fan. Are you sure it's PSU fan and not some
other one?
 
It's an Antec power supply for 350W. And I do hear more noise than before.
At first, I thought that the excessive noise was coming from the case fans
(I have 2), but turning them off did not solve the noise problem.
Also, I noticed that the hard drive (Western Digital 80GB with 8MB buffer)
was getting quite hot. I thought there was something wrong with the hard
drive, but my other hard drive (Western Digital 20GB) was getting just as
hot. I can't even keep my fingers on them when the system is on.
Can this also be the power source's fault?
Thanks
 
It's an Antec power supply for 350W. And I do hear more noise than before.
At first, I thought that the excessive noise was coming from the case fans
(I have 2), but turning them off did not solve the noise problem.
Also, I noticed that the hard drive (Western Digital 80GB with 8MB buffer)
was getting quite hot. I thought there was something wrong with the hard
drive, but my other hard drive (Western Digital 20GB) was getting just as
hot. I can't even keep my fingers on them when the system is on.
Can this also be the power source's fault?
Click to expand...

You have very bad ventilation in your box and need a lot
more airflow!
http://w1.857.telia.com/~u85710476/docs/image/example/pcvent.png
 
I have a 120mm fan in front of the hard drives (air in), and there's another
120mm fan in the back (air out). The MB temperature is hardly ever above
40C, and the CPU (P-IV 2.4GHz overclocked to 2.6GHz) temperature is even
less (usually around 33-35C). The hard drives are the only things that get
really hot. I tried opening the cover and turning the system on. As soon as
it was on, the hard drives got hot, even the 20GB one that wasn't
spinning....
 
I have a 120mm fan in front of the hard drives (air in), and there's another
120mm fan in the back (air out). The MB temperature is hardly ever above
40C, and the CPU (P-IV 2.4GHz overclocked to 2.6GHz) temperature is even
less (usually around 33-35C). The hard drives are the only things that get
really hot. I tried opening the cover and turning the system on. As soon as
it was on, the hard drives got hot, even the 20GB one that wasn't
spinning....
Click to expand...

The drives should normally not go over 40C and never over 50C.
My drives is about 10 degrees over room temperature.
You can measure the temperature with the drives internally temp probe.
 
I can hardly keep my hand on the drives, so I'd say they are at least at 60C
as soon as the power is on.
 
I can hardly keep my hand on the drives, so I'd say
they are at least at 60C as soon as the power is on.
Click to expand...

Then they are dead very soon!
Most drives have a max of 55C and some max 60C,
but the life span should be very short over 50C.
The goal is under 40C.
You really have to make better ventilation around the drives.
Something must be wrong planned in your computer case.
Here a little neat program to check the temperature on your drives.
http://private.peterlink.ru/tochinov/download.html
 
Thanks but my hard drives do not have the temperature check capability.

As for the ventilation, I don't think that's the problem. The hard drives
get hot as soon as the power is on and even when the case is open....
 
Thanks but my hard drives do not have the temperature check capability.
Click to expand...

Oh, they are very old?

As for the ventilation, I don't think that's the problem.
Click to expand...

That _IS_ really the problem.

The hard drives get hot as soon as the power is on
Click to expand...

No I don't think so. Impossible.

and even when the case is open....
Click to expand...

Yes that's normal and depends on lack of ventilation.
With the case open you don't get any airflow at all.
The drives must be mounted with a space between them
so the air can pass without problem between them.
The drives really need good air flow.
 
The hard drives get hot as soon as the power is on
No I don't think so. Impossible.
Click to expand...

That happens within a 10-15 second span. I put my hand on the drive and
turned the power on, the drive gets hot within 10 seconds or so.
I'm also posting this on one hardware forum and some people suggested that
it could be indeed the power source that was causing this problem.
I've had these same hard drives for over a year now and never had any
overheating problems before.
 
That happens within a 10-15 second span. I put my hand on the drive and
turned the power on, the drive gets hot within 10 seconds or so.
I'm also posting this on one hardware forum and some people suggested that
it could be indeed the power source that was causing this problem.
I've had these same hard drives for over a year now and never had any
overheating problems before.
Click to expand...

You mean that the chips on the PCB get hot or the metal frame of
the whole drive gets hot? The chips will get hot in a short
period of time, but the frame should not.

Use a multimeter to take voltage readings at power supply plugs.

Your front fan can't be moving much air if your prior estimates
are correct. If the front fan is behind a filter, remove the
filter as a temporary measure, and if you can't find a way to
increase airflow, keep the filter off. If there is no filter,
look at air intake flow retrictions such as the bezel openings or
metal grill. With a fan in front of the drives you could/should
expect the drives to feel cool to the touch on the frame, only
moderately warm on the drive controller chip.

I'm still not certain that the fan in the PSU is failing but
since you report it making more noise you might swap that fan.
However some ball-bearing fans do make a slight rumbling sound
when they go below a certain RPM range, but determining this
remotely without another fan for compaison isn't possible, except
by manually hooking up fan to a different power source to
increase RPM, see if the noise changes, decreases in some
frequencies rather than increasing as with other fans.

Since the system is still running OK (implied since you made no
mention of other problems) the odds are that the PSU itself is
still ok too, but you could also unplug it, remove it, open it,
and inspect the output filter caps (on the PCB near the wiring
harness connections) for failure (domed, swollen, vented top,
leaky or residue). Do not open the PSU if you're not comfortable
doing so, some people would advise just buying another PSU but
that does seem premature at this point.
 
You mean that the chips on the PCB get hot or the metal frame of
the whole drive gets hot? The chips will get hot in a short
period of time, but the frame should not.
Click to expand...

the frame is cool but when I put my hand underneath the drive -- that's
where it's really hot. As I mentioned, I've had these drives for quite some
time and never experienced this until just recently.

I also did a simple test... turned the system off, opened the case, put my
hand under the hard drive and turned the power back on. By the time the
system got past the 30-second OS selection screen (I have 2 OS installed),
the drive was already pretty hot (about 45 seconds since the power on).
After about 20 minutes it became so hot that I couldn't keep my hand under
the drive. Then I turned the system off and about 15-20 seconds later the
drive underneath was already back to the room temperature....

I also tried running the system with the drives out of the case.... they
were getting as hot.
 
the frame is cool but when I put my hand underneath the drive -- that's
where it's really hot. As I mentioned, I've had these drives for quite some
time and never experienced this until just recently.
Click to expand...

Or maybe just never noticed?

How hot do you think they SHOULD be?

Your drives are new enough that you should be able to find software to
monitor their temperature.


Have a nice week...

Trent©

Follow Joan Rivers' example --- get pre-embalmed!
 
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