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davelanger

macrumors 6502a
Original poster
Mar 25, 2009
832
4
The electrical buzzing sound in the back of the pro near the power socket is normal right? It kind of sounds like one of those bug zappers you see on decks.
 
A power supply isn't really meant to make zappy sounds - get thee unplugged, and to an Apple Store!

Weird thing just happened, the light I have in the room with my computer, I turned that light off and the buzz from the power supply stopped.

Oh btw its not making the zapping sound, its the sound when the zapper is not zapping, you know that hum it makes?

It looks like the light is causing the issue, its one of those fluorescent lamps. I moved it to a new outlet but its still making the sound.

Is this going to hurt the computer?
 
My Mac Pro Buzzes too, but it stops if I bang the side.

Can't find out where it is doing it and it's doing my head in!
 
Your switch is wired incorrectly or the lamp has a wiring fault. Have an electrician take a look see if you get the buzzing when with any device is plugged into that outlet.

Also, get the Mac Pro on a UPS asap! https://forums.macrumors.com/threads/1004739/

I only have a surge protector on my pro, I guess that is not good enough eh?
I swapped out my lamp for another one I had, and using the newer lamp does not cause the buzzing issue, so it must be the lamp.

Thats for your help and advice everyone.
 
I only have a surge protector on my pro, I guess that is not good enough eh?
I swapped out my lamp for another one I had, and using the newer lamp does not cause the buzzing issue, so it must be the lamp.

Thats for your help and advice everyone.

Did the buzzing sound something like this:
https://files.me.com/christianschmeer/n4kqzz.mov

?

Also, is there any way to make sure the electricity going towards the Mac Pro is exactly the right voltage? Would a surge protector do this? My flat is quite old and I think the wiring is pretty crappy :/
 
I only have a surge protector on my pro, I guess that is not good enough eh?
I swapped out my lamp for another one I had, and using the newer lamp does not cause the buzzing issue, so it must be the lamp.

Thats for your help and advice everyone.

I know I'm the minority on this, but I see absolutely no reason to spend bundles of cash on a UPS. Unless you live in an area especially prone to power outages, I don't see the need for battery backup. I live in an area where we experience, at most, 1 to 2 power outages per year. My $30 power strip does just fine for me.

As for all the "clean power" claims some of those power supplies have, I don't buy into that either. I'm no electrician, but I do live with one, and they have said those claims are false. If the power coming into your house is bad, some power strip isn't going to magically fix it and provide you with "perfect" power. You're better off calling an electrician and getting your wiring fixed properly.

It's just like the story with Monster Power HDMI cables. So many people are fooled into purchasing $100+ cables, that are identical to ones you can find on MonoPrice for about $10.
 
Did the buzzing sound something like this:
https://files.me.com/christianschmeer/n4kqzz.mov

?

Also, is there any way to make sure the electricity going towards the Mac Pro is exactly the right voltage? Would a surge protector do this? My flat is quite old and I think the wiring is pretty crappy :/

That is pretty much it, I did listen to the lamp and the same sound was coming from it. I think its because the lamp in one of those dimmer lamps.

The newer lamp is just on or off, and does not make that sound or cause my mac to make the sound. I think the lamp was causing the problem
 
I know I'm the minority on this, but I see absolutely no reason to spend bundles of cash on a UPS. Unless you live in an area especially prone to power outages, I don't see the need for battery backup. I live in an area where we experience, at most, 1 to 2 power outages per year. My $30 power strip does just fine for me.

As for all the "clean power" claims some of those power supplies have, I don't buy into that either. I'm no electrician, but I do live with one, and they have said those claims are false. If the power coming into your house is bad, some power strip isn't going to magically fix it and provide you with "perfect" power. You're better off calling an electrician and getting your wiring fixed properly.

It's just like the story with Monster Power HDMI cables. So many people are fooled into purchasing $100+ cables, that are identical to ones you can find on MonoPrice for about $10.

I personally can't afford to *not* use one. There are a lot of old buildings where I live, including the ones I work in. There have been many times where blips and drops have sent drives offline or everything off completely. But my Mac Pro and drives keep on going. Especially not good when you're in the middle of a long video render/export.
 
I personally can't afford to *not* use one. There are a lot of old buildings where I live, including the ones I work in. There have been many times where blips and drops have sent drives offline or everything off completely. But my Mac Pro and drives keep on going. Especially not good when you're in the middle of a long video render/export.

Yeah, that makes sense. If you're in a building, you can't exactly fix all the wiring. I won't totally discount UPS power supplies, I'm just very lucky I live in a home with good power.
 
Yeah, that makes sense. If you're in a building, you can't exactly fix all the wiring. I won't totally discount UPS power supplies, I'm just very lucky I live in a home with good power.

You are lucky! The wiring in my current building is so bad. And I was happy to have my UPS when hurricane Earl passed through here, just so I could turn on my wireless.
 
I know I'm the minority on this, but I see absolutely no reason to spend bundles of cash on a UPS. Unless you live in an area especially prone to power outages, I don't see the need for battery backup. I live in an area where we experience, at most, 1 to 2 power outages per year. My $30 power strip does just fine for me.
Even if you're not experiencing much in the way of outages, you may be experiencing an AC undervolt condition known as brownouts, and they can damage electronics over time.

No surge suppressor made can protect you from this, but a good UPS can (super cheap units = not so much). You need at least a Line Interactive model, as it has an auto transformer in it to pull up the voltage before it drops enough to switch the power source to the battery + inverter.

Please understand, that this is mentioned as another reason beyond the ability to shut down the system properly if there is a power outage (which most associate with having a UPS for).

That is pretty much it, I did listen to the lamp and the same sound was coming from it. I think its because the lamp in one of those dimmer lamps.
Those types of lamps can introduce noise which can be heard in a transformer (PSU). What you did is the right thing to do (get it off of the same circuit). ;)
 
Those types of lamps can introduce noise which can be heard in a transformer (PSU). What you did is the right thing to do (get it off of the same circuit). ;)

I have the same sound, even when no lamps are connected what's up with that :(

Also, doesn't this surge protector do brownout correction?

http://www.apcc.com/products/family/index.cfm?id=67
"Automatic voltage regulation for protection against brownouts and overvoltages.
Features: Automatic Voltage Regulation (AVR), Brownout correction, Overvoltage Correction, Status Indicator LED's, Surge Protection"

This site has it for 35 pounds. Basically sounds like a UPS without the battery/backup power function. Does that seem like a good purchase for use with a Mac Pro in a big building (200 people) from the 60's with bad wiring (I live in London, UK)? http://www.micomonline.co.uk/products.asp?partno=LE1200I&go
 
I'm getting that noise even when when nothing else in the room is plugged in. The Pro is on a surge protector and I unplugged everything from it, but still can hear that noise. Is it really supposed to be silent besides the fans? Every laptop I've owned has made that buzz too.
 
I have the same sound, even when no lamps are connected what's up with that :(

Also, doesn't this surge protector do brownout correction?

http://www.apcc.com/products/family/index.cfm?id=67
"Automatic voltage regulation for protection against brownouts and overvoltages.
Features: Automatic Voltage Regulation (AVR), Brownout correction, Overvoltage Correction, Status Indicator LED's, Surge Protection"

This site has it for 35 pounds. Basically sounds like a UPS without the battery/backup power function. Does that seem like a good purchase for use with a Mac Pro in a big building (200 people) from the 60's with bad wiring (I live in London, UK)? http://www.micomonline.co.uk/products.asp?partno=LE1200I&go
That unit is more than just a surge suppressor, and is far less common (example of a decent surge only unit). It's a surge + auto transformer, which is basically a Line Interactive UPS minus the battery pack and inverter.

I'm getting that noise even when when nothing else in the room is plugged in. The Pro is on a surge protector and I unplugged everything from it, but still can hear that noise. Is it really supposed to be silent besides the fans? Every laptop I've owned has made that buzz too.
Are you sure the circuit is completely unloaded with anything but the MP?

I ask, as some older buildings would share a circuit with more than a single room (usually fewer circuits in the breaker panel/fuse box, and each is a larger value). So you might want to turn off the system, turn off the breaker, and see what other outlets may be on it in other rooms (BTW, this can include ceiling fixtures). This can include CCFL bulbs (light fixtures) and ceiling fans can also generate that kind of noise on the circuit (just turn off the switch to check if either of these is the source if you have any of these on the circuit).

It's also possible that your unit is noisy (not all that uncommon in recent years due to cost cutting and uneven Quality Control). Unfortunately the MP's haven't been immune to this, including their PSU's (2008 systems had a bad batch or two that caused problems, so it may have re-surfaced again as they're after the cheapest supplier/s that they can find).
 
Are you sure the circuit is completely unloaded with anything but the MP?

I ask, as some older buildings would share a circuit with more than a single room (usually fewer circuits in the breaker panel/fuse box, and each is a larger value).

This is exactly how my flat is wired. The kitchen and bedroom share the same circuit, so you can't use the toaster when the A/C is on. I think the people that designed our building were in the final stages of dementia.
 
This is exactly how my flat is wired. The kitchen and bedroom share the same circuit, so you can't use the toaster when the A/C is on. I think the people that designed our building were in the final stages of dementia.
Nah, people just didn't have all the crap then we do now. :eek: So the circuits were planned on those presumptions (days before computers, home theater systems, air conditioning,...). ;) :p
 
Are you sure the circuit is completely unloaded with anything but the MP?

I ask, as some older buildings would share a circuit with more than a single room (usually fewer circuits in the breaker panel/fuse box, and each is a larger value). So you might want to turn off the system, turn off the breaker, and see what other outlets may be on it in other rooms (BTW, this can include ceiling fixtures). This can include CCFL bulbs (light fixtures) and ceiling fans can also generate that kind of noise on the circuit (just turn off the switch to check if either of these is the source if you have any of these on the circuit).

It's also possible that your unit is noisy (not all that uncommon in recent years due to cost cutting and uneven Quality Control). Unfortunately the MP's haven't been immune to this, including their PSU's (2008 systems had a bad batch or two that caused problems, so it may have re-surfaced again as they're after the cheapest supplier/s that they can find).

I can't be certain that the socket is unloaded since I'm in an apartment and have no idea how they wired this place. I only hear the noise when I'm right up against it (and would've had no idea were it not for this thread :p ). Is that true for you OP? Or can you hear it over the fans at a few feet distance?
 
I can't be certain that the socket is unloaded since I'm in an apartment and have no idea how they wired this place. I only hear the noise when I'm right up against it (and would've had no idea were it not for this thread :p ). Is that true for you OP? Or can you hear it over the fans at a few feet distance?

Sounds exactly like your case. If I put my head towards the back of the Mac Pro, I can hear the buzzing. I went to the fuse box and switched off everything but the sockets and made sure only the Mac Pro was plugged into one of the sockets, but it still buzzes...

That unit is more than just a surge suppressor, and is far less common (example of a decent surge only unit). It's a surge + auto transformer, which is basically a Line Interactive UPS minus the battery pack and inverter.

I don't need any backup power function, as I never had any power outages within the last 2 years, but if my flat is in a big building (200 people) and it's from the 60's (and wiring in the UK seems to be pretty bad in general), wouldn't I want something more than just a surge suppressor? Do you think the APC surge + auto transformer would be a good purchase for a Mac Pro in my case?
 
I can't be certain that the socket is unloaded since I'm in an apartment and have no idea how they wired this place.
Do you pay the electric bill directly (not included in the rental fee, but to whatever power company is your provider)?

If so, you have your own panel and meter (panel is usually inside, the meter outside so it can be read without having to enter the dwelling), which means you don't share circuits with other units. It's when the power is included in the rent, that this may not be the case (i.e. homes that were converted to apartments could be such cases).

I don't need any backup power function, as I never had any power outages within the last 2 years, but if my flat is in a big building (200 people) and it's from the 60's (and wiring in the UK seems to be pretty bad in general), wouldn't I want something more than just a surge suppressor? Do you think the APC surge + auto transformer would be a good purchase for a Mac Pro in my case?
Yes, you should use more than a surge suppressor. The unit you linked is more than that (has an auto transformer in it), so it would help with brownouts.

The UPS is still an option (Online unit can exceed the protection offered by the unit you linked, as it's always running off of the battery + inverter and the output is a pure sine wave), but it is of course more expensive.

If you are interested in the latter, Eaton is available in the UK, and make decent products. Past that, I'd stick with APC or Tripp Lite, and go refurbished if at all possible to save funds (I've never had a problem with a refurbished unit so far). Not sure how large the market is for refurbished Eaton, but you can find it for APC and Tripp Lite (Tripp Lite units are usually less expensive, but APC's batteries are cheaper, which tends to make APC cheaper over time; say 12 years using a 3 year replacement cycle for the batteries).
 
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