Power munching

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reedOsama

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Can someone please explain to me how the explanation of pc hardware power consumption works:

Is it measured per hour... minute... second

what does "according to ATI the 5*** has a TDP of 108 Watts" mean

Im more concerned now that electricity prices are going up:(
 
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The best explanation of Watt and TDP is given on the wiki pages:
http://en.wikipedia.org/wiki/Watt
http://en.wikipedia.org/wiki/Thermal_design_power

Watt is not measured per hour/minute/second/anything. It's a rate at which energy is transferred. It's more like speed than like distance. If you want to know how many units of energy you are actually using, you need to look at Watt Hours (Wh). If you leave a 100Watt light bulb on for an hour, it's going to use 100Wh of electricity.

If the ATI card says it has a TDP of 108 Watts, it means it will need to dissipate energy at a maximum rate of 108Watts. If 108Watt is coming out as heat, at least 108Watt is coming in as electricity, so if you leave your graphics card running at 100% capacity for a month it's going to cost you: 108 [Watt] * 24 [hour/day] * 30 [day/month] * (1/1000) [kWatt / Watt] * 0.75 [Rand/kWatt.hour] = R58.32

Of course the card won't be needing that much power while it's idle.
 
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If I remember right electricity is measured and handled in kWh,so 1000Wh = 1 unit or .75cents so realistically speaking with a 130% power price increase you'd be paying R1.80 per 10 hours of frantic 100% GPU-usage gaming :P
 
It's more like 200% (or 3x).

45% increase three years in a row:

1 x 1.45 x 1.45 x 1.45 = 3.04

That's a 200% increase like Madman88 correctly says just a little bit down.
 
psichron said:
It's more like 200% (or 3x).

45% increase three years in a row:

1 x 1.45 x 1.45 x 1.45 = 3.04

That's a 200% increase like Madman88 correctly says just a little bit down.
Click to expand...

3.03? surely that's a 300% increase?

and remember that the gpu uses 27watts during idle... and probably 40watts during 2D, about 50-60watts during light 3D.

It's only when you have a lot of stuff being processed will it feel the burn.
 
No, 3x = 200% increase.

R1 + 200% = R3
R1 x 3 = R3

Considering the average home electricity bill is probably around R1200/month now, you better start asking your boss for a raise over the next to years.
 
My understanding is that the 45% is a hike on the current 2009 rates.

psichron said:
Watt is not measured per hour/minute/second/anything. It's a rate at which energy is transferred. It's more like speed than like distance. If you want to know how many units of energy you are actually using, you need to look at Watt Hours (Wh). If you leave a 100Watt light bulb on for an hour, it's going to use 100Wh of electricity.
Click to expand...

So in effect, for general calculations, base it on an hour. If you want to calculate how much power your PC is consuming in a month, add up the wattage it is drawing out the wall socket and just do 24 x 7 x 4 and that'll be nice rough estimate.

My machine chews about 70KWh per month. It does 89-105W at idle when the power save is on leaving cores running @ 800MHz. When set to normal mode @ 3.2GHz it shows 125W, at 100% CPU it shows 165W. The old PC did 155W constantly and 169W indicated under full load.

I wonder what my CRT monitor is eating. :P

I'd love to ditch my house lighting for decent 12V-24V setup using solar panels, etc., but just the cost of the panel is ridiculous. Expect these to get even more expensive as people turn to them.
 
There was also a 33% hike this year.

Look at it this way. Those solar panels should pay for themselves even quicker with the coming increases.
 
Some arb rough calculations...

Say for example I have around 500W of bulbs throughout the house, with some being power saving items. If I run them 24/7 that'd be around 336KWh for max lighting or R265 per month in costs. In 3 years time, if the calcs are correct, I could pay R756 per month on lighting.

Note it's actually tons less because of course lights aren't running constantly.

It'd take 24 months to cover the costs for a large enough solar system to handle that amount of power constantly and with good batteries that don't need constant replacing.

That's not too bad. The problem with this approach is that people are more reluctant to cough up, say, R20K in one go as compared to paying the monthly electricity bill.

But I must have a look around again and see what is up in the renewable energy field. There's a McDonalds a few hundred metres from my house. I could get free old oil and run a bio-fuel BigMac generator. :D
 
TheRift said:
Some arb rough calculations...

Say for example I have around 500W of bulbs throughout the house, with some being power saving items. If I run them 24/7 that'd be around 336KWh for max lighting or R265 per month in costs. In 3 years time, if the calcs are correct, I could pay R756 per month on lighting.

Note it's actually tons less because of course lights aren't running constantly.

It'd take 24 months to cover the costs for a large enough solar system to handle that amount of power constantly and with good batteries that don't need constant replacing.

That's not too bad. The problem with this approach is that people are more reluctant to cough up, say, R20K in one go as compared to paying the monthly electricity bill.

But I must have a look around again and see what is up in the renewable energy field. There's a McDonalds a few hundred metres from my house. I could get free old oil and run a bio-fuel BigMac generator. :D
Click to expand...

it took me a WHILE too work this one out but i think your need for a solar system with batteries is what confused me.

THanks psichron for the help (Im still trying to process it) but all I needed to really know was if my PC was a major power chower in the house.
 
Wahaha! :D Yeah, uhm, if I had my own solar system... :D That was a typo of note :D

Right, solar panels then. :) You definitely need batteries.
 
reedOsama said:
THanks psichron for the help (Im still trying to process it) but all I needed to really know was if my PC was a major power chower in the house.
Click to expand...

It won't be. Look towards TV, fridge, stove and the geyser. Fridge and geyser will be the ones eating alot of power.
 
the most power hungry things are those that produce heat...

ovens, geysers, tumble driers, heaters etc.
 
Fair enough :D Don't worry, you're safe, it should be minimal compared to the rest of the household.
 
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