Cost efficiency of a computer PSU based on watts rating

[Larry James 901346]

Can someone tell me if there a difference between running a 1000 watt computer PSU and a 1000 watt light bulb? For instance, I’m sure if you burn a 1000 watt light bulb you’d burn the maximum amount of energy all the time (1000 watts). Using the full 1000 watts might be substantially more costly at the end of the month if you didn’t need all the light produced all the time, but of course as long as the light was turned on it would burn the 1000 watts.

 

Now my question about a computer, while 1000 watt is probably an overkill, I’m thinking I should get a bigger wattage PSU than my current 400 watt power supply. If I got a higher wattage PSU, is there a chance that the wattage rating would burn the power based on the immediate computer load (components installed and intensity of the immediate applications) rather than a constant use based on the 1000 watt rating? During off peak times when I might not have many USB devices plugged in and not be running graphic intensive applications, would it be possible that the 1000 watt PSU would be less bucks (or equal to) the cost of the 400 watt PSU? Or would the 1000 watt PSU cost the same amount for the 24 hour operation of the computer as running a 1000 watt light bulb for the month.

 

By the way, I’m looking at purchasing an 800 watt PSU and I’ll be upgrading my 88000gts graphics card soon. I just replaced the case with an AXP 600 that has lots of room and cooling facility. I probably don’t need the 800 watts at present, but with time I will be replacing the CPU and motherboard.

 

Is there a chance (or scenario) where a higher wattage PSU might actually be more cost efficient at the end of the month and possible burn less electrical dollars because of less strain to keep up?

 

Thanks in advance for anyone that can understand my question and provide input.

 

-- L. James

 

--

L. D. James

[email protected]

http://www.apollo3.com/~ljames

[Darrol Larrok 1140797]

My understanding is that the wattage indicates capacity, not constant usage.

[Larry James 901346]

My understanding is that the wattage indicates capacity, not constant usage.

 

Thanks... that's what I thought. At first I was buying PSU in increments based on what I thought I might immediately need. But now I'm gong to buy a bigger increment. I see one that looks nice and quiet that will probably be useful for a long time.

 

-- L. James

 

--

L. D. James

[email protected]

www.apollo3.com/~ljames

[Darrol Larrok 1140797]

That's probably a good idea. Make sure you have a decent amount of overhead too, as they lose capacity over time.

[Larry James 901346]

That's probably a good idea. Make sure you have a decent amount of overhead too, as they lose capacity over time.

 

I'm sure that's what has happened to my current one.

 

-- L. James

 

--

L. D. James

[email protected]

www.apollo3.com/~ljames

[Darrol Larrok 1140797]

Probably, definitely irritating.

[Paul Tutty]

 

Edited May 27, 2022 at 02:58 AM by Paul Tutty

[Darrol Larrok 1140797]

With regard to cost-saving, it's worth noting that if you turn your PC off at night, and it enters a low-power stat when idle, it's power use is unlikely to add up to much.

[Larry James 901346]

Wikipedia has a good article on efficiency and power ratings, so I won't ramble on about it as the short answer has already been stated. However, if you're concerned about saving some energy (and coin), then I can solidly recommend the BFG LS-550 as a sturdy, well-designed PSU that runs well at all power outputs (efficiency curve). I use it at home after seeing it recommended on a review of 500W-550W PSUs.

 

Amazon is currently selling this PSU for just under US$82. Then, what I do, is connect a surge-protecting smart power strip through an electricity monitor so that I can be aware of the electricity being used by my PC and peripherals and when I press the sleep button on my keyboard, the smart power strip automatically turns off power to all peripherals. So now you know your PC energy usage and you save money each time you power down to a low-power state (as turning off completely can degrade the PSU slowly and can in fact eventually be a cause of failure).

 

Thanks for the input, Paul. Great links. I’ll be getting the Electricity Monitor and the 5 power strip adapters combination from Amazon. The review of the BFG LS-550 is great. It’s probably not that noisy. But because of the number of computers in the shop, I’m doing what I can to control the noise. I’m looking at the AXP PowerReal 850W (review and price) for a number of reasons which includes the quietness that is included in the description. I believe the blue LED will look nice in the AXP 600 case which is designed to see the insides (with the designed ventilation feature). While I did think it was unlikely, I hated to think of constantly burning 800watts 24 hours during idle times.

 

I’ll use the meter to study other ways of energy efficiency designs around the shop. A couple of the computers are over 10 years old. I look forward to seeing if it would save if I replace some of them.

 

By the way I started looking into these immediate upgrades when FSX recently started malfunctioning. Locking the FPS from the unlimited setting it was and blowing out the 8800GTS card with compressed air appears to have resolved the immediate FSX issue. Blowing out the 8800GTS brought the card from 80C to 61C during the heaviest load.

 

-- L. James

 

--

L. D. James

[email protected]

http://www.apollo3.com/~ljames

[Ernesto Alvarez 818262]

you would be surprised how much all those little flashing/steady lights that stay on at night start to add up. yeah the main power may be off on the appliance, but its still using up electricity.

 

cost savings on getting a smart device can be anywhere from a few dollars to almost $100 or more if you really have a ton of appliances.

 

might not mean much to folks making big money or dont pay bills, but to folks on a budget, that extra savings goes a long way

[Larry James 901346]

you would be surprised how much all those little flashing/steady lights that stay on at night start to add up. yeah the main power may be off on the appliance, but its still using up electricity.

 

cost savings on getting a smart device can be anywhere from a few dollars to almost $100 or more if you really have a ton of appliances.

 

might not mean much to folks making big money or dont pay bills, but to folks on a budget, that extra savings goes a long way

 

If it's more than a few of dollars to run two or three LED's on a computer, you're right. I'd be extremely surprised. Do you have a source for being able to calculate this cost?

 

I have recently started calculating the cost of some of the components in my shop. I'm sure the 875 watt PSU is more than the capacity I'll need for a long time. I'll most likely look for a lower wattage power supply. There's a chance the cosmetic effect might bury some inefficiencies of it over other power supplies that are only efficiency orientated. But I hardly think the actual cost of powering the LED to be a major financial cost burden.

 

Of course I could be wrong on this latter and would appreciate some actually cost formulas to be able to study.

 

-- L. James

 

--

L. D. James

[email protected]

http://www.apollo3.com/~ljames

[Ivan Kovacevic 920456]

Typical LED current is 25mA, at 5 volts, that's 125mW, or 0.125Watts. When we factor in the PSU 80% efficiency, that's about 0.156W, that's about 1.4 KWh per year if the LED was running non-stop. Now, in Serbia, 1KWh in the most expensive domestic tariff is about 0.06EUR, which is 0.07 US$.

 

 

So, I'd be saving about 7 cents per year for every LED I turn off.