How much power my computer uses: measured

[pm]

For Christmas, my mother game a gizmo which lets me measure the power of appliances. It?s the ?La Crosse Technology Cost Control? (http://www.lacrossetechnology.com/products/spec_items/3362.html ). I calibrated it against several of the house appliances that have watt ratings written on them - like the electric kettle and the iron and it came out within 5% of their ratings that's next to the "CE" logo on the bottoms.

I tried it on my computer and I was really surprised by the results. I have a 3.4GHz Pentium 4, 1GB DRAM, nVidia 5900 video cad, Asus P4C800-E motherboard, 100 GB WD HD, 1 CD-RW and 1 DVD+/-RW, and then a 21" NEC FP1355 CRT.

Computer with monitor, both in StandBy: 72W
Computer with monitor off, idling in Windows: 98W
Computer with monitor on, idling in Windows: 202W
Computer with monitor on, playing World of Warcraft: 265W
Computer and monitor together, max power measured over a month?s worth of use: 290W

A lot lower than I would have guessed. Like I said, it is very accurate on other things though, so I assume it is accurate in this as well.

 

[CheesePoofs]

Your link's broken, but thats interesting.

Were you measuring just your computer's usage or both the computer and monitor? I've believe that monitors use ~70 watts when displaying an image, so if you measured both the computer and monitor, it must be miscallibrated.

 

[pm]

Originally posted by: CheesePoofs
Your link's broken, but thats interesting.

Fixed. It parsed it with the parenthesis as part of the link.

Were you measuring just your computer's usage or both the computer and monitor? I've believe that monitors use ~70 watts when displaying an image, so if you measured both the computer and monitor, it must be miscallibrated.

I have a fairly large monitor (ok, it weighs about 80lbs, so it's super large). NEC rates it at ~120W. I'm measuring about 104W... which is pretty close... especially considering that all engineers always quote worst-case numbers for specs.

If it's miscalibrated, it's not badly incorrect. It might be off by a little but it's not off by a lot.

 

[CheesePoofs]

Did you have the part where it said with/without monitor before? If you didn't ..... im a complete idiot. I somehow managed to completely miss that.

 

[Rand]

I use a similar power monitor from Seasonic, it's quite handy.

For reference, my system hits 215W under load with a single Hitchi 19" CRT on.
A64 3200+
GF 6600GT
1x CDRW
1x DVD
2 7200RPM HDD's (Maxtor D740X & WD1200JB)
SB Audigy2
2GB DRAM
Gigabyte NF4 (K8NF-9)

 

[FinalLasttt]

Interesting!
I wonder how much power does a laptop take?
100W ?

 

[flamingelephant]

what type and size of PSU?

 

[Amaroque]

Measured by my UPS...

The monitor is not hooked up to the UPS, only the PSU is plugged into this UPS.

Idling in windows 173W
CPU load 100% (Prime95) 227W
6800GT @ Ultra running Rthdribl 275W

You can see the current hardware I am running in my sig.

 

[Pr0d1gy]

Measure how much juice your PSU is putting out & let us know how much & what kind it is.

 

[pm]

Originally posted by: Pr0d1gy
Measure how much juice your PSU is putting out & let us know how much & what kind it is.

That's a harder problem - the power supply puts out DC - not AC - so the gizmo won't work. One could use a clamp ammeter, but you'd need to measure each rail in turn with both voltage and current... it would take a little while.

I plugged the gizmo into the wall and read the numbers off and posted them here. 🙂Figuring out the efficiency of my aging power supply is a harder task.

My power supply is an Antec 350W as I recall. Nothing special.

I wonder how much power does a laptop take?

My IBM Thinkpad T40 is reading 56W idling in Windows. Throttling is completely disabled (it's on AC and I have it set to the max when it's plugged into a wall) and the LCD is on max brightness. The battery is charging currently too. T40 review - since IBM doesn't have it listed any more.

http://arstechnica.com/reviews/hardware/t40.ars/1

So:
IBM T40 laptop idling in Windows w/ LCD off: 46W
IBM T40 laptop idling in Windows w/ LCD on: 56W
IBM T40 laptop playing World of Warcraft (*): 62W

(*) It plays ok at 800x600 with all details off. Great framerates, plenty of artifacting and the game terrain looks less than wonderful, but you can play it.

 

[Jeraden]

That device sounds cool, I might have to get one too!

 

[randomlinh]

kill-a-watt is another one you can use too.

 

[JimPhelpsMI]

Hi, Your reading are probably right on. Now you know how ridiculous some of the claims in this forum are. Jim

 

[Matthias99]

Originally posted by: JimPhelpsMI
Hi, Your reading are probably right on. Now you know how ridiculous some of the claims in this forum are. Jim

Also, these numbers are measuring how much power the PSU pulls from the wall, which counts the waste heat it's dumping because of inefficiency (unless this was already taken into account in his post, but I didn'ts ee that). The actual usage of his system is probably ~25-35% lower than the numbers given.

 

[Pr0d1gy]

So it is pretty safe to say a 500w Aspire PSU could run this computer without any problems:

AMD 3200+ 939 Winnie
MSI Neo2 Platinum
Xtasy x800xt
Corsair Xpert 1gb
Raptor 74gb SATA
WD Caviar 200gb IDE
Benq 56x CD-Rom

 

[ribbon13]

My rig draws 775w accounting for the %72 efficiency. TEC cooling is not cost effective.

 

[Byte]

Wattage ratting from a crappy brand doesn't mean anything, get a decent 300-350w from a reliable brand like Antec or Fortron.

Originally posted by: Pr0d1gy
So it is pretty safe to say a 500w Aspire PSU could run this computer without any problems:

AMD 3200+ 939 Winnie
MSI Neo2 Platinum
Xtasy x800xt
Corsair Xpert 1gb
Raptor 74gb SATA
WD Caviar 200gb IDE
Benq 56x CD-Rom

 

[mwmorph]

Originally posted by: FinalLasttt
Interesting!
I wonder how much power does a laptop take?
100W ?

on the back of most laptops next ot the ac plug inlet, there is a rating for watts used. mine says 90watts but is probably inaccurate. i leave it on to compile and the heeat in the socket melted the plastic of the tip of the ac adapter. needless to say, im never buying a hp laptop with a desktop p4 ever again.