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Thread ID: 48237 2004-08-17 14:23:00 how much power is this computer using? robsonde (120) Press F1
Post ID Timestamp Content User
262639 2004-08-17 14:23:00 The system is my web server / router.

a k6II 300MHz cpu
ga586tx3 motherboard (old)
64Mb ram PC100
a 4Mb 2D pci video card that is very old.
a compack flash card type I for a hard drive.
a external modem.
a network card.


nothing else.
no cdrom, no moniter, no keyboard, no fans, no speaker , no blinkin lights.


would this setup use more than 50W ???
is there an easy way to mesure what is being used??
robsonde (120)
262640 2004-08-17 14:27:00 assuming 50W is being used then is my cost of running right??

50W * 24 hours per day * 31 day = 37200W

which is 37.2 units per month at a cost of about 16 cents = $5.58
robsonde (120)
262641 2004-08-17 19:26:00 Your maths are very close. It is $5.95 for the month or 0.8 cents/hour Raymondo (5284)
262642 2004-08-17 21:36:00 I have a very similar rig to robsonde that I leave on 24 / 7, except mine has 128MB Ram.

That's good to know how much it does cost each month to leave on.
Chilling_Silence (9)
262643 2004-08-18 05:10:00 I thought the $$ math would be about right


the real question is how many watts is the system using??

i have use 50W in my math but i have no idea if that is right or even close.
robsonde (120)
262644 2004-08-18 09:38:00 The only easy way is to use a multimeter, if you have one, that will measure AC current. Bear in mind that small meters don't like large current flow. If your PC was in fact a 50w device the current flow at 230V would be 220mA. Dick Smith have a small $30 digital multimeter in stock that will measure AC current in the range 400uA to 400mA. A 400mA upper limit would restrict it to a 90 watt load at mains supply voltage.
I can't be much more help than that.
Raymondo (5284)
262645 2004-08-18 09:53:00 Sorry. That DSE meter I mentioned is Cat. No Q1569 and it is actually $39.00 Raymondo (5284)
262646 2004-08-18 10:30:00 The meter has to be in series with the phase connection, which means it has to be connected before power-up. Just getting the 230v input to that position is not easy and involves modifying the 230v wiring to the PSU.

Its most probable that the inrush current of the power supply would pop the 400 mA fuse of the meter. Switchmode supplies have quite a high inrush (it would be quite a few amps, not mA) for a few cycles.

And its not a very "safe" activity unless you really know what you are doing.
godfather (25)
262647 2004-08-19 02:11:00 Interrupted phase tapons are useful things. :D So are AVOs. ;-)

You can (at a considerable price) buy clipon ammeters, which you can use with a short extension cord made with trurip with the phase wire separated.

Silicon Chip are running a series on building a power monitor which would be ideal. Of course, this (a) is a kit requiring some skill, and (b) will cost a hundred or so.
Graham L (2)
262648 2004-08-19 02:33:00 [ fears showing great lack of understanding] is there such a thing as a device that sits between the mains plug and the computer's power lead [ like and extension box] that shows how much current is being drawn? This would also take into account the power used by the power supply fan[s] ?:| KatiMike (242)
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