Vostro - Noisy Fan at boot

I have just got a Vostro 200 Desktop and have noticed that the fans
(processor and case fan) are very noisy for about 2 seconds as the PC is
booting up and then they quiten down to normal whisper (well nearly) speed.

I realise its not a fault and I have heard other PC makes do this (like
Compaq PC's) but I am just wondering why its designed like that?

The Dimension 2400 I am replacing never did this the fan was always whisper
quiet.

Hopefully in the next BIOS update for the Vostro they might adjust it so
they don't do this in a future BIOS update.

Andy.

 

My 3000 didn't do it but my XPS400 does. Shouldn't be a problem. The temp
and fan speed controls probably aren't kicking in until somewhere during
bootup. I don't think the 2400 or 3000 had variablr speed fams controlled by
temp sensors but my XPS and newer Dells do.

 

I wonder if I should do this silly thing. Each of the fans have 3 wires one
would be Ground the other 2 I am predicting are +5v & the other +12v I
wonder if it would be a silly thing to cut the +12v one - that would almost
definitely stop the loud fan noise at startup. - (and void the warranty more
than likely!)

Andy.

 

You would probably kill the fan speed control too. When I am running a heavy
graphics load the fan revs up to prvide extra cooling and you can hear
it...about the same sound level as when computer is first started.. So
yours might "quietly" burn up

 

My XPS does that briefly when I boot/reboot - which I seldom do! Mine runs
24/7. How often are you rebooting?

 

Every day. Sometimes if I boot at night or in the morning it sounds really
loud.

Andy.

 

Hi!

It could be for any number of reasons. One that comes to my mind is a
self-test of some kind. These fans usually have tach leads that report speed
to the system and its fan controller. Sometimes they are only accurate at
"full throttle".

As the fans age, it could also be used as a cheap measure to assure
starting. Computer fans have a bad habit of getting dry bearings and failing
entirely.

William

 

Hi!

You should definitely *not* do that. The wires going to the fan are DC+, DC-
and a tachometer output. If you cut the voltage, the fan simply won't run at
all and your equipment will cook in very short order.

Killing the tach line may result in a system that complains of a dead fan,
runs the fan up to its maximum speed as a measure of defense against
overheating or simply lets the fan stay at too low of a speed while the
thing it should be cooling gets way too hot and dies.

William

 

Live with it. For a couple of seconds or so, the fans run at full speed and
sensors monitor the current they consume when running at full speed. If the
current is below a certain level, the fans are not running properly and most
well-engineered systems will halt rather than boot up, to prevent overheating.

The Dimension 2400, though decently engineered for a budget-priced computer,
does not have all the engineering safeguards found in more expensive models.

.... Ben Myers

 

Thanks for that advice - I wont then.

Andy.

 

The Vostro works out cheaper than what the Dimension 2400 cost at the
time! - Its alright saying live with it, but I am also at the point of
thinking that the fans will have a longer life if they stayed at a lower
speed all the time rather than speeding up like this every time the PC is
booted apart from that it gives the 'impression' that there is a fault with
the PC as its starting and also the fact that its bloody noisy if I start or
reboot the PC in the middle of the night or in the morning.

Andy.

 

In my experience when Processor fans get old they screech like mad when they
get old so imagine that in the future when they are running at maximum speed
the noise
will be even worse than it is now!

I would say a good system will monitor fan RPM levels at all times
accurately and not only when the PC is starting up.


Andy.

 

When the fans start screeching, replace them. As a preventive measure, used
compressed air and q-tips to clean the fans with some regularity. How regular?
How dirty is the environment? Are there smokers in the area? What about dogs
and cats or other furry animals? ... Ben Myers

 

See my other comment about fans. Really and truly... live with it. A couple
of seconds of high speed fan noise can't be that bothersome. And when you hear
the high speed fan noise at power up, you can be reassured that the fans are
working OK. Dell has done this with a lot of its models, but not the low end
Dimension 2350, 2400, 3000. Most recently I set up a Dimension 4700 for
someone. Same deal. Loud fan noise for a couple of seconds when the system
boots or reboots... Ben Myers

 

Why would you keep starting and rebooting the machine? That does more
damage than the fan noise ever will.

The fans are originally designed to run at full speed. The reason they
start fast and then slow down is because of the way the control circuit
is designed. They run up to full speed as a test of operational current.
Say there is a big hairball in one. When it turns on the machine will
discover that the fan isn't working and shut down due to the sudden
current spike and lack of tach signal from the fan. It also will
throttle the fans back until the heat inside the system get to the trip
point, at that time the fans will speed up to cool the system. Without
that higher speed ability you WILL cook the system. It is a protective
measure that also audibly tells YOU that " Hey see the fans WORK". I
wish many of the other models did the same. What would worry me is NOT
hearing those fans when the machine first starts up.

--
Steve W.
Near Cooperstown, New York
NRA Member
Pacifism - The theory that if they'd fed
Jeffrey Dahmer enough human flesh,
he'd have become a vegan.

 

Bull! - My previous PC Dimension 2400 bought in 2002 fan never were loud
(when booting up or at any other time) and went like a dream all these
years, no overheating or anything. Everybody used to comment that when it
was on they had to do a double take because they couldn't hear it!

So far at least 3 people has heard the fans when I turned on the PC and are
saying 'thats loud should they sound like that?' .

Andy.

 

You are missing the point so eloquently made by several of us. If the fan noise
lasts for a couple of seconds, then settles down and the computer runs quietly,
what is the problem? The computer is simply doing its job of testing the fans
to make sure they are working OK. Once again, live with the two seconds of loud
fan noise when the computer boots up. This is not BULL! This is reality. How
else can it be stated so you will understand and accept it?

Do you keep rebooting the computer to show your friends how noisy it is when it
starts up?

The Dimension 2400 lacked the startup fan checking algorithms, so it started up
quietly. So what? You have a different model of computer now.

I will argue no further with you... Ben Myers

 

Good, I am glad you are not going to argue no more - I weren't arguing
anyway I was just saying things as it is. You put up with the noise if you
like don't mean to say I have to. I am stating this for people who may have
been disillusioned into thing because all Dell's have been quiet in the past
that it is going to be the case that the new ones are just as quiet.

I had my hands on one computer once, I cant remember what make/model now but
I remember going to the manufacturers website and downloading a BIOS upgrade
for the main board amongst other fixes (one to support a higher CPU) one of
the fixes stated that it fixed 'when booting up PC fan runs at maximum speed
after installation of this BIOS upgrade fan(s) will run at a reduced speed'
and sure enough it did so it can be and has been done.

Andy.

 

BULL! Yourself. You sure have a LOT of experience with TWO whole
computers from Dell. WOW. Try having owned about 50 different machines
from just about every maker. Plus servicing at least 500 Compaq's for
the state.
Guess what, The EVOs from Compaq and the Thinkcentres from IBM BOTH run
the fans up to full power and then drop them back once the hardware
knows they are operating. That makes about 400 of them that do the same
thing.
Some of the other Dells I've owned do the same thing. The Dimension 8200
that is playing my MP3s right now does it as well.
If you have such a problem with it send the machine back. OR understand
that it is designed to operate that way. Your 2400 wasn't.

 

you seem to miss my point that I am saying that my Dimension 2400 (P4 2ghz)
fan always ran at low speed and in the Dell diagnostics showed a temp sensor
and fan speed - the same can be applied to the Vostro 200 with 1.6 Duo Core
I am sure without any damage - I am even going to look into reducing the
Vostro's fans from 2 to 1 because I don't really think that this
configuration needs 2 fans running. The processor and temperature in my
Vostro run no hotter than my Dimension 2400 which only had one fan so why
should I have to have 2 on my Vostro?

Andy.