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Question 1kw power suppy

A

Airbrushkid

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I was wondering how your light bill went up when you started using a 1 kw power supply?
 
It didn't, and it won't. A 1kw PSU will draw the same amount of power as a 550 watt PSU when only 300 watts is being drawn from it. The only way your electric bill will go up from switching to a 1kw PSU is if you start taxing the thing. If your machine only requires 280 watts most of the time then the PSU will only draw as much energy as is needed to put out 260 watts. If your machine idled near a kilowatt then yeah, you'd see a slight increase in your electric bill vs. a system that only used 500 watts max. Under heavy use, you'll only see increases if your using it a lot and keep it drawing that much power all the time. I've got a 1200 watt PSU in my machine and currently the total power draw of my machine (idling) is 270 watts. Under full load conditions the power draw will increase to somewhere between 500 and 600 watts.
 
Mine does :D

Then again I run them at 1000W, which as Dan points out you won't be. Sure if the unit is horribly inefficient at low loads and you are at low loads it could draw more power than a more correctly sized unit,but that difference really is going to be only a few watts.
 
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When my system had dual 4870 X2's in it on the Skulltrail setup, with 4 Raptors I was pulling about 1100 watts under load. With 3 GeForce GTX 280 OC cards in 3-Way SLI it dropped to about 900 watts. Now that I'm running an overclocked Core i7 920 with only one Radeon HD 5970 (at present anyway) I'm using FAR less power. I'm still using that same Thermaltake ToughPower 1200 watt PSU though. I've got the Coolermaster Real Power Pro 1000 sitting in my Skulltrail box, which has been relegated to doing server work these days.
 
What Dan_D said is mostly true. Typically PSU's, operate most efficiently at around 50% of there max load. So say you have two power supplies 500 watts and 1000 watts both at 85% efficiency at half load and they both operate at 83% at quarter load.

If your computer draws a load of 250 watts (DC) then you pull 294 watts of AC power from the wall with your 500 watt PSU and 301 watts with the 1000 watt PSU. (I know half load is the actual draw from the wall but I think it is easier to demonstrate the opposite way.

Thats why it is better to use a power supply that will be between 1/2 and 3/4 of what your max system draw is.
 
Well I didn't want to get into all that which is why I left the wording of my post a bit vague. But yes, more power supply than you need means that your PSU won't be taxed as hard as a lighter PSU which can only output the minimum your system needs at most.
 
Thank you guys. I am planning on 2 to 3 GTX 285's and a ssd's plus 2 hard drives. Not to mention all water cooled.
 
Airbrushkid said:
Thank you guys. I am planning on 2 to 3 GTX 285's and a ssd's plus 2 hard drives. Not to mention all water cooled.
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Well obviously that will make your power bill go up compared to your current system (and I hope you plan on upgrading your CPU, motherboard, and RAM as well).
 
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