Go Back   EcoModder Forum > AltModding > Saving@Home
Register Now
 Register Now
 


Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 12-07-2008, 01:21 AM   #1 (permalink)
MechE
 
Join Date: Dec 2007
Location: Bay Area
Posts: 1,151

The Miata - '01 Mazda MX-5 Miata
Thanks: 0
Thanked 21 Times in 18 Posts
Power Supply Efficiency

I'm setting up a new computer... And I took a peek at my power supply....

100-127V - 8A

So that's fully loaded power....

So 110V *8A = 880Watts

The supply is rated to deliver 300W max...

That's to say, fully loaded my power supply has an efficiency of 34% Yes, fully loaded is one of the least efficient zones - but still, 34%?

I found a similar power supply (same model and power reqs/specs with a couple different connectors) that claims 70% minimum efficiency
ATX12V-G300BT (Bestec ATX-300-12EB3 Power Supply)

Any other explanation? What's your box say?

__________________
Cars have not created a new problem. They merely made more urgent the necessity to solve existing ones.
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 12-07-2008, 01:54 AM   #2 (permalink)
Master EcoModder
 
Join Date: Aug 2008
Location: South Dakota
Posts: 460

WonderWagon - '94 Ford Escort LX
Last 3: 51.52 mpg (US)

DaBluOne - '99 Ford Escort SE
90 day: 48.97 mpg (US)

DaRedOne - '99 Ford Escort ZX2 Hot
Thanks: 0
Thanked 15 Times in 4 Posts
Look for articles about multiple Power Supplies compared at Tom's Hardware: Hardware News, Tests and Reviews

No time now - got to leave in a minute.
Will look up the specific article and write more on this tomorrow.
__________________
  Reply With Quote
Old 12-07-2008, 08:06 AM   #3 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,887

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,413
Thanked 2,908 Times in 1,823 Posts
Hi,

A much better source of info about power supplies is one of my other haunts: Silent PC Review.

silentpcreview.com | Everything about Silent / Quiet Computers

Typical older units were in the 65-75% efficiency range (though some are lower), and now 80-85% are fairly common. A few units are approaching 90% now; and it also depends a lot on your actual consumption. Most computers are 100-200 watts of DC consumption, so add ~25-30% to that for the AC use.
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 12-07-2008, 02:30 PM   #4 (permalink)
Master EcoModder
 
Join Date: Aug 2008
Location: South Dakota
Posts: 460

WonderWagon - '94 Ford Escort LX
Last 3: 51.52 mpg (US)

DaBluOne - '99 Ford Escort SE
90 day: 48.97 mpg (US)

DaRedOne - '99 Ford Escort ZX2 Hot
Thanks: 0
Thanked 15 Times in 4 Posts
Quote:
Originally Posted by NeilBlanchard View Post
A much better source of info about power supplies is one of my other haunts: Silent PC Review.

silentpcreview.com | Everything about Silent / Quiet Computers
Wasn't aware of that site. Good find, looks like their tests are as through as Tom's Hardware.

Here a link that takes you straight to the Power Supply Articles & Reviews at Tom's Hardware.

And here is a link that takes you straight to the Power Supply Articles & Reviews at Silent PC Review.

Silent PC's article about Power Supply Fundamentals looks particularly good.

The specific article at Tom's Hardware that I had in mind is
Inadequate and Deceptive Product Labeling: Comparison of 21 Power Supplies
Quote:
In spite of the high end-user retail prices, our lab technicians were surprised by the test results. No fewer than 6 power supplies struggled under full load: 3 of the candidates simply went up in smoke, while the other 3 shut down prematurely. The "black sheep" among all the test participants was Maxtron, with the TOP-520P4. According to the manufacturer's specifications, this power supply is represented to be capable of withstanding 520 watts - divided up over the corresponding voltage ranges. However, in our test, it ceased working at 446 watts. Completely dead!
Lawyers, politicians, statisticians and Power Supply Manufacturers - they all tend to bend the truth and a significant number of each one tell out and out lies. Take manufacturer's specification numbers with a great, big block of salt. Shop for specific units that have performed well in tests conducted at one of the above sites. Or shop for brands that consistently perform well in multiple tests conducted at one of the above sites.
__________________
  Reply With Quote
Old 12-07-2008, 06:10 PM   #5 (permalink)
Administrator
 
Daox's Avatar
 
Join Date: Dec 2007
Location: Germantown, WI
Posts: 11,173

CM400E - '81 Honda CM400E
90 day: 51.49 mpg (US)

Daox's Grey Prius - '04 Toyota Prius
Team Toyota
90 day: 49.53 mpg (US)

Daox's Insight - '00 Honda Insight
90 day: 64.33 mpg (US)

Swarthy - '14 Mitsubishi Mirage DE
Mitsubishi
90 day: 56.69 mpg (US)
Thanks: 2,471
Thanked 2,537 Times in 1,529 Posts
Take a look at The 80 PLUS Program | Home for efficiency info on different maker's power supplies. I've been looking into this a lot recently. My power supply is probably 8 years old or so, it claims 70% efficiency at full load. I look forward to finding a new 85+% for whenever I do a new build.

Its pretty horrible when you look at the numbers. 70% efficiency and my computer at idle consumes 150W. That means I'm wasting 45 watts as a best case scenario!
__________________
Current project: A better alternator delete
  Reply With Quote
Old 12-07-2008, 07:43 PM   #6 (permalink)
Master EcoModder
 
roflwaffle's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 1,490

Camryaro - '92 Toyota Camry LE V6
90 day: 31.12 mpg (US)

Red - '00 Honda Insight

Prius - '05 Toyota Prius

3 - '18 Tesla Model 3
90 day: 152.47 mpg (US)
Thanks: 349
Thanked 120 Times in 79 Posts
Quote:
Originally Posted by trebuchet03 View Post
What's your box say?
Supposedly it's ~80% efficient at full load. Not bad for a $5 PS.
  Reply With Quote
Old 12-08-2008, 10:19 AM   #7 (permalink)
Master EcoModder
 
Join Date: Sep 2008
Location: Texas
Posts: 632
Thanks: 0
Thanked 25 Times in 23 Posts
The 8A is the fuse rating. It has nothing to do with actual load. Also, you'll need a True-RMS meter to accurately measure the current as it is very nonlinear.
__________________
If America manages to eliminate obesity, we would save as much fuel as if every American were to stop driving for three days every year. To be slender like Tiffany Yep is to be a real hypermiler...

Allie Moore and I have a combined carbon footprint much smaller than that of one average American...
  Reply With Quote
Old 12-14-2008, 11:52 PM   #8 (permalink)
Master EcoModder
 
The Atomic Ass's Avatar
 
Join Date: Oct 2008
Location: Mason, OH
Posts: 535

Priinocchio - '17 Toyota Prius Two Eco
90 day: 66.31 mpg (US)
Thanks: 11
Thanked 20 Times in 17 Posts
Quote:
Originally Posted by Daox View Post
Its pretty horrible when you look at the numbers. 70% efficiency and my computer at idle consumes 150W. That means I'm wasting 45 watts as a best case scenario!
Have you verified that number by a Kill-A-Watt or other meter? I HIGHLY doubt you'll be drawing 150w at idle, unless your monitor is factored in. With my Mac Mini, (smaller than your computer I imagine, but keep reading), 2 external hard drives, external DVD-writer on idle, USB hub with a cellphone charging off it, and a broadband modem, all while running file-sharing to the tune of 10-15mbps, (A lot of disk access), was only drawing about 65 watts average, at the wall, through a UPS. I only get up to about 150w with my monitor running.

Trebuchet: The 8A is maximum burst current draw. As in when all the motors in all the hard drives, dvd drives, and the processor are all drawing maximum load, while the PS capacitors are charging up, which is what happens in a start-up condition, when you have enough equipment tacked on to run the PS at full load afterwards.
__________________

Last edited by The Atomic Ass; 12-15-2008 at 12:00 AM..
  Reply With Quote
Old 12-15-2008, 12:48 PM   #9 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,887

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,413
Thanked 2,908 Times in 1,823 Posts
Hi,

Mac Mini's and the new iMac's are exceptionally efficient and use very little power. 150watts is a bit higher than typical, but with a gaming video card, it is not hard to get the idle in that range.

Check out Silent PC Review for all sorts of good info on power supplies and efficiencies.
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 12-15-2008, 01:26 PM   #10 (permalink)
Administrator
 
Daox's Avatar
 
Join Date: Dec 2007
Location: Germantown, WI
Posts: 11,173

CM400E - '81 Honda CM400E
90 day: 51.49 mpg (US)

Daox's Grey Prius - '04 Toyota Prius
Team Toyota
90 day: 49.53 mpg (US)

Daox's Insight - '00 Honda Insight
90 day: 64.33 mpg (US)

Swarthy - '14 Mitsubishi Mirage DE
Mitsubishi
90 day: 56.69 mpg (US)
Thanks: 2,471
Thanked 2,537 Times in 1,529 Posts
Yep, thats what the ol kill-a-watt tells me.

I just reformatted this weekend and ended up ripping out my sound card and extra network card. I'm now using onboard sound and lan. This dropped me down to 141W at idle.

Specs are:

Athlon xp 2500 barton core
Radeon X800 GTO
Seagate Cheetah ST336607LW 37gb scsi hd
Western Digital Caviar SE16 WD2500KS 250gb sata hd
Enermax EG365P-VE power supply


I'd be interested in knowing how much juice the scsi card and HD eat up.

__________________
Current project: A better alternator delete
  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Power Steering delete for fuel economy gain - anyone done it? bennelson EcoModding Central 92 01-27-2017 03:58 PM
Converting power steering to electric power steering Daox EcoModding Central 54 01-17-2017 06:16 PM
Electric car conversion: Project ForkenSwift MetroMPG Fossil Fuel Free 1041 07-28-2014 09:19 AM
Getting more efficiency out of a ZX2. Small list of mods and driving tips for it. koihoshi EcoModding Central 9 07-20-2008 04:26 AM
Automotive X Prize - would a modded Civic VX make it? Krieg EcoModding Central 31 01-02-2008 07:06 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com