New mac pro slight buzz from psu. Is this normal?

[nigel1210]

Just received a nehalem mac and there is a slight buzzing noise coming from the psu.

You can only really hear it when you go close to the back of the mac pro.

Is this normal?

 

[nanofrog]

It can be, but a better PSU won't. I'm not sure about the new MP's, but I think they may be using the same PSU from the '08 model.

By chance do you have access to a UPS or a Line Conditioner?
If so, plug the computer into one of those, and see if the hum dissappears (A/C hum, due to poor power quality).

 

[Tallest Skil]

It can be, but a better PSU won't. I'm not sure about the new MP's, but I think they may be using the same PSU from the '08 model.

By chance do you have access to a UPS or a Line Conditioner?
If so, plug the computer into one of those, and see if the hum dissappears (A/C hum, due to poor power quality).

It's a different PSU; they're in the high eighties on the efficiency scale as opposed to the one in the aught eight Mac Pros.

 

[nanofrog]

It's a different PSU; they're in the high eighties on the efficiency scale as opposed to the one in the aught eight Mac Pros.

Where did you spot this information?

 

[Tallest Skil]

Where did you spot this information?

http://images.apple.com/environment/resources/pdf/Mac-Pro-Environmental-Report.pdf

Bottom of the first page. You can access this from the Mac Pro's "Environment" page.

Now, granted, it is Apple putting this out, but they can't say it unless it's true... because the greenies would be on them in a heartbeat.

 

[nanofrog]

http://images.apple.com/environment/resources/pdf/Mac-Pro-Environmental-Report.pdf

Bottom of the first page. You can access this from the Mac Pro's "Environment" page.

Now, granted, it is Apple putting this out, but they can't say it unless it's true... because the greenies would be on them in a heartbeat.

Thanks for the link.

You do realize, that's peak efficiency though. No PSU holds the same efficiency across the entire load. It's a curve. Efficiency usually peaks somewhere in the ~500 - 750W range, depending on the design.

 

[belvdr]

Thanks for the link.

You do realize, that's peak efficiency though. No PSU holds the same efficiency across the entire load. It's a curve. Efficiency usually peaks somewhere in the ~500 - 750W range, depending on the design.

I always heard that any power supply is at its most efficient during a full load. Never tested though, because I never cared.

 

[nanofrog]

I always heard that any power supply is at its most efficient during a full load. Never tested though, because I never cared.

Not quite, but close. About 65 - 75% of full load. Efficiency dumps after that. Not quite so wonderful before either.

 

[nigel1210]

There swapping it out anyway.

Wonder if the replacement will still be the same.

 

[Infrared]

Just received a nehalem mac and there is a slight buzzing noise coming from the psu.

You can only really hear it when you go close to the back of the mac pro.

Is this normal?

Yes. There's nothing to worry about. Apple use the best quality bees.

 

[jjahshik32]

A slight buzz is normal.

 

[soldierblue]

Yeah, totally normal. I had a chat with PC Power and Cooling about just this a few weeks ago. Normal fluctuations in the power draw of the system can cause the coils to vibrate or capacitors to whine.

 

[nigel1210]

lol@infrared

This is weird as my pc psu doesn't do it at all, and their plugged into the same Surge strip.

 

[soldierblue]

Some brands tend to do it, some don't. Seasonic is a particular offender, they're the OEM for Corsair and PCP&C among others. Maybe the same OEM manufactured these?