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gtext
29th March 2008, 01:59 PM
Wondering if anyone with a 2008 Mac Pro that could lay there hands on a current draw meter, could check the wattage drawn when the Mac Pro is turned off.
I'm getting 41 to 43 watts being drawn when the Mac is off and all cables unplugged.

I asked this question on the Apple forums. Someone in the US replied on their lower voltage (120 volts) that when off it was 6 watts and sleeping 11 watts.
On our 240 volt supply this should be about 3 watts off and 5.5 watts. Using the formula (volts x amps = watts. ie. higher voltage lower watts.
Correct me if I'm wrong here.

Just like to get a real reading from someone in Australia. Seems very high to me.

funkmaster_dan
29th March 2008, 03:07 PM
I think you've confused yourself with Ohm's law, Current (amps) = Volts / Resistance. If the power supply is doing the same amount of work, it should consume approximately the same amount of energy, regardless of the input voltage.

gtext
29th March 2008, 03:20 PM
I think you've confused yourself with Ohm's law, Current (amps) = Volts / Resistance. If the power supply is doing the same amount of work, it should consume approximately the same amount of energy, regardless of the input voltage.

Used this as a reference Electric power - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Wattage)

Anyway if if that persons mac is drawing 6 watt compared to mine drawing 43 watt that's a huge difference.

geektechnu
29th March 2008, 03:28 PM
No power supply is 100% efficient (the best consumer PSU's rank in as 80-85%), so any basic calculations you do will be off.

I do recall seeing figures somewhere that most power supplies achieve higher efficiency with higher AC input voltage. As far as I can remember it's a few percent at optimum load. Possibly a larger difference for low loads.

funkmaster_dan
29th March 2008, 03:30 PM
Used this as a reference Electric power - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Wattage)
Well there you go, I stant corrected. However, I still belive the wattage should be the same, the Australian version PSU would just be drawing less amps over the higher voltage line.

gtext
29th March 2008, 03:34 PM
[QUOTE= However, I still belive the wattage should be the same, the Australian version PSU would just be drawing less amps over the higher voltage line.[/QUOTE]

That does make sense. So the wattage should be the same for both voltages?

Brains
29th March 2008, 04:22 PM
Danamania has a Jaycar power-load meter (awesome little units, $40-ish) and a Mac Pro 8-core, and she's done the tests you're after ... I recall her telling us the figures in IRC one time, but stuffed if I can remember what she said, except that she was suprised to find it pulled less current when it was in sleep mode than it did when it was shut down. I think. PM her, she'd have the figures scribbled down somewhere, she's that kind of gal :)

gtext
29th March 2008, 04:51 PM
Danamania has a Jaycar power-load meter (awesome little units, $40-ish) and a Mac Pro 8-core, and she's done the tests you're after ... I recall her telling us the figures in IRC one time, but stuffed if I can remember what she said, except that she was suprised to find it pulled less current when it was in sleep mode than it did when it was shut down. I think. PM her, she'd have the figures scribbled down somewhere, she's that kind of gal :)

Thanks Brains. That's the same power meter I'm using.
I'll follow up on your suggestion.

leon
29th March 2008, 04:59 PM
Sorry to get off topic but it appears danamania is no longer a registered member of the forum. If true that would be very sad indeed as she has helped me many times, even fairly recently.

gtext
29th March 2008, 05:06 PM
Sorry to get off topic but it appears danamania is no longer a registered member of the forum. If true that would be very sad indeed as she has helped me many times, even fairly recently.

That's ok leon.
I was about to reply that I discovered the same as you.

semaja2
29th March 2008, 05:18 PM
Just be glad it isnt a Acer server ;) 140 watts just to have the PSUs connected and when the serve is powered up its 400watts

soulman
29th March 2008, 05:18 PM
I'm getting 41 to 43 watts being drawn when the Mac is off and all cables unplugged.That is way off normal. I would suggest either a faulty power supply or some issue with your measurement &/or calculation.

What did you use for measurement and what, if any calculations did you make?

gtext
29th March 2008, 05:28 PM
That is way off normal. I would suggest either a faulty power supply or some issue with your measurement &/or calculation.

What did you use for measurement and what, if any calculations did you make?

Used one of these meters Jaycar Electronics (http://www.jaycar.com.au/productView.asp?ID=MS6115&CATID=&keywords=power+meter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=)
Seems accurate on other appliances.

Yes seems a high reading to me too.

Might see the reseller where I purchased it and/or Apple next week.

soulman
29th March 2008, 05:33 PM
Used one of these meters Jaycar Electronics (http://www.jaycar.com.au/productView.asp?ID=MS6115&CATID=&keywords=power+meter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=)
Seems accurate on other appliances.So you are measuring current? What is the actual value?

gtext
29th March 2008, 05:47 PM
So you are measuring current? What is the actual value?

Using this meter Jaycar Electronics (http://www.jaycar.com.au/productView.asp?ID=MS6115&CATID=&keywords=power+meter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=) and reading in watts with all the other cables disconnected shows 41 - 43 watts with the mac turned off.
Someone I contacted on the Apple forum said his using the same sort of meter read 6 watts turned off. 11 watts sleeping. Mine shows 44 - 45 sleeping.

Running seems ok at 170 watts idling.

forgie
29th March 2008, 05:48 PM
Using this meter Jaycar Electronics (http://www.jaycar.com.au/productView.asp?ID=MS6115&CATID=&keywords=power+meter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=) and reading in watts with all the other cables disconnected shows 41 - 43 watts with the mac turned off.
Is that maximum, or average?

What does it read when it's asleep?

gtext
29th March 2008, 05:56 PM
Is that maximum, or average?

What does it read when it's asleep?

41 - 43 maximum when turned of. Should be drawing little at this stage.

44 - 45 sleeping. Although running seems ok at about 170 no load.

soulman
29th March 2008, 05:58 PM
...mine shows 44 - 45 sleeping.

Running seems ok at 170 watts idling.Agreed. The others are really whacko though. I will have a similar meter this week sometime. Will report my figures when I have them.

gtext
31st March 2008, 08:06 AM
Agreed. The others are really whacko though. I will have a similar meter this week sometime. Will report my figures when I have them.

Thanks soulman. I'd appreciate that. The off and sleep draw is higher that I would have expected.

soulman
3rd April 2008, 11:43 AM
41 - 43 maximum when turned of. Should be drawing little at this stage.

44 - 45 sleeping. Although running seems ok at about 170 no load.I just got my power meter and am dismayed to report that I am getting similar figures on mine. A little lower - high 30s for both readings - but still far too high.

One more small but nonetheless niggling problem with this machine. <sigh> The most money I've spent on a Mac and by far the most disappointing Mac purchase I've ever made.

gtext
3rd April 2008, 08:15 PM
Wow!! Thanks for checking that Soulman.

At least I now know I'm not the only one.
Is that with all cables except the power disconnected? Apparently the firewire outlets supply power all the time so I believe.

As I said in an earlier post someone in the US stated on their 125 volt supply 6 watt off & 11 watt sleeping. If that is true I wonder why the big variation. He was quoting 170 watt idling which is similar to mine.
One of my concerns was the Mac drawing that amount switched off with no fans running for cooling.

I spoke to Designwyse where I purchased it but they weren't much help as Apple don't supply any such specs to them. They suggested contacting Apple to discuss with them.

Sorry to see you've had some other issues and hope you can get them sorted out.
What types of problems exactly?

Not had any issues with this one apart from this query up to now, but I do see others having some issues on the forums. Reboot from sleep I didn't experience.

It would be nice to compare with some others with new Mac Pro's regarding this power usage.

I'll post here if I find out anything further. Thanks again.

kurka
22nd April 2008, 09:01 PM
I just bought a Mac Pro with 2*2.8 Ghz processors. I also bought a powermeter to measure how much my Mac would draw when in sleep mode, but was very surpsised to see that I got the same measures as mentioned in this thread. When completely shut down it draws between 38-40 watt and a little more when in sleep mode.

I have contacted Apple about this but they can not even tell me what the measures are supposed to be. All they can tell me is that I have to deliver it to service in order to get a proper measurement. But what is the point in doing that if it is designed to draw 40 watt when off?

Are there any other on this thread that has contacted Apple?

gtext
23rd April 2008, 01:51 AM
I just bought a Mac Pro with 2*2.8 Ghz processors. I also bought a powermeter to measure how much my Mac would draw when in sleep mode, but was very surpsised to see that I got the same measures as mentioned in this thread. When completely shut down it draws between 38-40 watt and a little more when in sleep mode.

I have contacted Apple about this but they can not even tell me what the measures are supposed to be. All they can tell me is that I have to deliver it to service in order to get a proper measurement. But what is the point in doing that if it is designed to draw 40 watt when off?

Are there any other on this thread that has contacted Apple?

Actually I just contacted apple this past day.
The guy I spoke to on the 133 MAC number didn't really know but just gave his opinion that it sounded ok. When I asked to speak to someone more knowledgeable he gave me a case number and got me to speak to a "Product Specialist. This guy said he didn't have the information at hand, but advised me to go to developer.apple.com, and look for a tech note on the Mac Pro with the information I needed. So far I've found nothing there.

Both these guys did say however that some components still draw even when switched off.
The wattage drawn when off can vary depending on the setup on each computer.

It would seem that this at least is not isolated to one computer and may well be the same for all.

As I said earlier in this thread a chap on the Apple forums in the US I think stated that he's drew 6 watts off & 11 watts sleeping. This started me questioning my 43 & 45 watts draw.

kurka
23rd April 2008, 05:58 AM
I guess they say it sounds ok since they won't admit that there is either something wrong or quite a design flaw. When you get a EnergyStar you shouldn't draw 40w when turned off.

I think I'll call Apple again to get the correct figures.

I have also read in other forums that the correct draw should be 5+ when off and 10-15 when sleeping.

gtext
23rd April 2008, 10:14 PM
I guess they say it sounds ok since they won't admit that there is either something wrong or quite a design flaw. When you get a EnergyStar you shouldn't draw 40w when turned off.

I think I'll call Apple again to get the correct figures.

I have also read in other forums that the correct draw should be 5+ when off and 10-15 when sleeping.

Agreed.

I thought I may have been an isolated case but there seems to be two others besides me.

The figures you have quoted are about what I expected. Not 40 plus watts.

Trouble is Apple don't or aren't admitting to having any details.
I guess the people on the phones only have what's available to them.

Need someone higher up to contact. Suggestions anyone?

kurka
7th May 2008, 05:40 PM
After 4 phonecalls to Apple I was finally lead to this page:
Apple - Environment - APES (http://www.apple.com/environment/resources/specs.html). For the Mac pro 2*3.0ghz the specifications are here: http://images.apple.com/environment/resources/pdf/APES_MacPro_8-core_7-20-07.pdf
and shows (section 5) that the Mac Pro should draw less than 2W when off and less than 9W in sleep mode. So now Mac is off to service :-(

forgie
7th May 2008, 05:54 PM
Hmmm. I've been meaning to grab a watt meter for some time.... I'd like to know exactly how much my Mac Pro is drawing too.....

gtext
7th May 2008, 06:38 PM
After 4 phonecalls to Apple I was finally lead to this page:
Apple - Environment - APES (http://www.apple.com/environment/resources/specs.html). For the Mac pro 2*3.0ghz the specifications are here: http://images.apple.com/environment/resources/pdf/APES_MacPro_8-core_7-20-07.pdf
and shows (section 5) that the Mac Pro should draw less than 2W when off and less than 9W in sleep mode. So now Mac is off to service :-(

I'd be really interested if you could post back how you go.

My only concern is the document's dated 20/7/07 before the Mac Pro (early 2008) came out.
Are these the specs for the previous model?

Anyway I wish you good luck with Apple.

soulman
7th May 2008, 09:05 PM
Yeah, well done kurka for persevering and getting somewhere! I would also be very interested to see how you go. Please do report your experience if you can.

gtext
19th May 2008, 11:09 AM
After 4 phonecalls to Apple I was finally lead to this page:
Apple - Environment - APES (http://www.apple.com/environment/resources/specs.html). For the Mac pro 2*3.0ghz the specifications are here: http://images.apple.com/environment/resources/pdf/APES_MacPro_8-core_7-20-07.pdf
and shows (section 5) that the Mac Pro should draw less than 2W when off and less than 9W in sleep mode. So now Mac is off to service :-(

Kuma. Any follow up news from Apple?

ghettro
21st May 2008, 01:06 AM
Gee that's pretty interesting, anyone know what is actually drawing the power when it is completely off? 40w is the same as leaving a light on.

kurka
28th May 2008, 10:06 PM
Sorry, but I haven't had time to deliver my mac to service yet. I don't want to be without it for a long time ;-)

jimdrum
28th May 2008, 10:18 PM
That does make sense. So the wattage should be the same for both voltages?

Yes, that's right. The wattage should be the same.

kurka
8th September 2008, 10:12 PM
At last: My Mac has been to service (InfoCare in Norway) and they confirmed that my Mac draws 35 W when turned off. They also tested on 3 other Macs they had there and they also measured the same. Easy case? No. Apple claimed that this is the way it is and that nothing will be done about it. And on top of that InfoCare will charge me for the investigation. About US$ 100 :-( Now, I don't know what to do... I'll try to call Apple again.. :-(