I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

In article .com,
(known to some as )
scribed...

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Some off-the-shelf no-name PC's (and even some of the name brands)
come with poor-quality switching supplies. Such supplies can be audibly
noisy, and the pitch can change as the load on the supply does.

If you truly suspect your power supply is the culprit, and it is a
standard ATX or whatever the current form factor is, you would do well
to invest some $$ (expect around $100 or so) in a better supply from a
reputable maker.

I've had outstanding results with supplies from PC Power and
Cooling (www.pcpowercooling.com). Another good name is Astec (hard to
find, but great stuff).

Happy hunting.





--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
http://www.bluefeathertech.com -- kyrrin a/t bluefeathertech d-o=t calm
"Salvadore Dali's computer has surreal ports..."

wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

bad Fan ?


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

On May 24, 7:25 pm, wrote:
I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

What make and model? Is it still under warranty? Have you listened
to another similar computer before you bought this one?

H. R. (Bob) Hofmann

wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Without a better description of "high pitch noise" it could be anything.
Where is the noise coming from? (Please don't respond "the computer.")
Do you hear it from the speakers? Is it coming from the fan vents in the
power supply? Does it sound mechanical in nature - like a metal on metal
noise - or is it a high pitched squeal that changes pitch or volume
before it disappears?

Rick

wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Quite likely to be the ferrite cores in the PSU 'singing' as a result of
magnetostriction.

Graham

"Eeyore" wrote in message
...


wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Quite likely to be the ferrite cores in the PSU 'singing' as a result of
magnetostriction.

Graham

How do you solve this? Will a coat of varnish stop them from singing? I have
a psu that sings in the 14-16khz range when it is on standby.

- Mike

Michael Kennedy wrote:

How do you solve this? Will a coat of varnish stop them from singing? I have
a PSU that sings in the 14-16 khz range when it is in standby.


The first thing you have to do is find the exact source of the noise.
A piece of small flexible plastic tubing will help. Put one end in your
ear, and use the other to probe the inductors and other components to
determine which is causing the problem. Depending on what you find will
determine the next steps.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

"Michael A. Terrell" wrote in message
...
Michael Kennedy wrote:

How do you solve this? Will a coat of varnish stop them from singing? I
have
a PSU that sings in the 14-16 khz range when it is in standby.


The first thing you have to do is find the exact source of the noise.
A piece of small flexible plastic tubing will help. Put one end in your
ear, and use the other to probe the inductors and other components to
determine which is causing the problem. Depending on what you find will
determine the next steps.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

I guess the question was more out of curiosity rather than actually reparing
it. It will probably be months before I have time to mess with that psu.

Michael Kennedy wrote:

I guess the question was more out of curiosity rather than actually repairing
it. It will probably be months before I have time to mess with that psu.


At least you know where to start! :-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

AcBel 450W. Yes still under warranty. No, I've not check this PSU
before I bought it.

On May 25, 8:53 am, "hr(bob) "
wrote:
On May 24, 7:25 pm, wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

What make and model? Is it still under warranty? Have you listened
to another similar computer before you bought this one?

H. R. (Bob) Hofmann

The issue I have is that it's not always giving the noise. And the
noise does not go away (once it started) with load. I had to reset
the machine a few time during boot up and after that, it goes away and
would not happen until the next boot up.

On May 25, 8:49 am, Dr. Anton T. Squeegee
wrote:
In article .com,
(known to some as )
scribed...

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Some off-the-shelf no-name PC's (and even some of the name brands)
come with poor-quality switching supplies. Such supplies can be audibly
noisy, and the pitch can change as the load on the supply does.

If you truly suspect your power supply is the culprit, and it is a
standard ATX or whatever the current form factor is, you would do well
to invest some $$ (expect around $100 or so) in a better supply from a
reputable maker.

I've had outstanding results with supplies from PC Power and
Cooling (www.pcpowercooling.com). Another good name is Astec (hard to
find, but great stuff).

Happy hunting.



--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)http://www.bluefeathertech.com-- kyrrin a/t bluefeathertech d-o=t calm
"Salvadore Dali's computer has surreal ports..."

Without a better description of "high pitch noise" it could be anything.
Where is the noise coming from? (Please don't respond "the computer.")
Do you hear it from the speakers?

Not the speakers.

Is it coming from the fan vents in the power supply?

Yes. It seems to be loudest from the fan vents of the PSU. I didn't
open the case to check though. I will do it tonight.

Does it sound mechanical in nature - like a metal on metal
noise - or is it a high pitched squeal that changes pitch or volume
before it disappears?

No.. it's like those old TV high pitch but not so high and loud.
definitely not mechanical. It does not disappear on its own. It
start when I boot up ... when I press the on button on the PC front.
Sometimes, it does not come. But when it does (which is more often
than not), I have to press the on button or the reset button or Ctrl-
Alt-Del to restart the computer. Sometimes, it goes away with 1
reset. Sometimes, after 2 or 3. But it does go away.

If the first time, I boot up and the noise does not come, it will not
come during the whole session when the PC is boot up.

But sometimes, when I first boot up, there is no noise.

Thanks.

Rick

What is that ? How to solve ?
Thanks.

Quite likely to be the ferrite cores in the PSU 'singing' as a result of
magnetostriction.

Graham

Michael Kennedy wrote:

"Eeyore" wrote
wrote:

I have a new PC and it comes with a high pitch noise ! but it does
not occur all the time.
When I power up, I get the noise (more often than not). But if I reset
the PC a few times, it will go away. But sometimes, when I power up,
I don't get the noise.
So it's not permanent.

Would like to hear from you what could be wrong ? Thanks.

Quite likely to be the ferrite cores in the PSU 'singing' as a result of
magnetostriction.


How do you solve this? Will a coat of varnish stop them from singing? I have
a psu that sings in the 14-16khz range when it is on standby.

Once you get a noisy one it seems to require replacement. The varnish might do
it if it was a vacuum varnish process !

Some ferrites also 'hiss' btw due to controller chip behaviour AIUI.

Graham

wrote:

What is that ? How to solve ?
Thanks.

Quite likely to be the ferrite cores in the PSU 'singing' as a result of
magnetostriction.

Graham

http://en.wikipedia.org/wiki/Magnetostriction

Not easy to solve. It may be a design issue. It might be a slightly duff batch
of ferrite.

Graham

wrote:

But sometimes, when I first boot up, there is no noise.

This thread is getting silly. You just bought the machine. It is under
warranty. If you are unhappy, take it back.

This is a DIY after 7 days. Have to do own troubleshooting. Can't
just return the whole machine. Please see things from other's
perspective.

Anyway, I change the PSU and still have the same problem. I then
change the Motherboard and it seems like the problem is solved.

On May 26, 8:59 am, Vey wrote:
wrote:
But sometimes, when I first boot up, there is no noise.

This thread is getting silly. You just bought the machine. It is under
warranty. If you are unhappy, take it back.