how many watts is my system using?

[Reloadron]

Originally Posted by JazzyJake

alright.
i said i had a 550w psu, and i had no clue what it was using, and he guessed around 300w and he said that would be like $80 a month running 24/7.
i really didn't think it could be considering i've had my rig for so long.
and my laptop folds for MPC also. Gotta use school connection/power for something...

That may be a bit of a high estimate. First you need to determine what you are paying for electricity. You need to look at a recent electric bill and muddle through it to find the cost per kilowatt hour. Electric bills can be confusing animals with things like Reclaimation, Delivery and a host of other charges. You only want the actual cost per KWH. Lets say you pay $0.10 or $0.15 per KWH.

Lets say the machine uses 500 Watts. Forget all the PSU calculator stuff as none of that takes into consideration use at assorted loads and PSU Efficiency. We only care about what we are using out of the wall outlet. I like 500 becuase it is a nice number. Therefore 500 Watts is 0.5 KWH. Therefore running 2 hours uses 1 KWH.

Now at 10 cents per kwh and you are using 12 kwh per day you are spending $1.20 per day or about $36.00 a month based on a 30 day month at ten cents per kwh. Using 15 cents per kwh figure about $54 a month.

Ron

[JazzyJake]

that makes sense, but my PC won't/doesn't use 500w all the time, correct?

[wtcnbrwndo4u]

Originally Posted by JazzyJake

that makes sense, but my PC won't/doesn't use 500w all the time, correct?

Yup. Back to the closer assumption, you will use around 260-280W on load, but when the computer is just sitting around, you'll be using around 100-120W.

[Reloadron]

Originally Posted by JazzyJake

that makes sense, but my PC won't/doesn't use 500w all the time, correct?

No it won't. The PSU will deliver to the system no more than it needs. Meaning a load on lets say 600 Watt PSU may be only 400 Watts. Now if we assume at a 400 Watt delivery the PSU is 80% efficient, the draw on the line side would be 500 Watts or 0.5 KWH. That is as I mentioned previously a very high estimate.

The other thing is what you actually pay per KWH. Ever muddle through an electric bill? Sheese, they love to complicate it. All you care about is actual cost per KWH. Cost like distribution/Delivery, Reclaimation, and other stuff is the same month to month.

Very few systems use even close to what the PSU is rated at. One of these days I have to chart an actual system looking at the actual draw at the wall outlet and chart it over a period of time.

Ron