DC programs make CPU consume more power?

[Shaka]

My dad's computer is a P3-750 and is on 24/7 acting as the router for the rest of the comps. I was thinking about putting SETI on it to do some crunching, but then I realized that perhaps SETI would cause his computer to consume more power than if it were just idling.

So does using DC programs like SETI cause a computer to consume more power? If so, is it negligible?

 

[Robor]

I don't think it's going to make a difference. AFAIK your CPU is going to be getting the same amount of voltage either way.

 

[JonB]

An Intel PIII would see some increase in power consumption, the greatest evidence of that would be the small but noticeable rise in CPU temperature. More power equals more heat.

Would you notice it on an Electric Bill? No, since it runs 24/7 already.

The same is true for any of the processors newer than a 486 chip. The older processors pretty much ran full speed whether they were doing anything or not.

Processors for laptops are very good at reducing power consumption to match CPU load requests. It makes the battery last a LOT longer. I have a laptop running SETI right now that keeps the CPU fan running about 75% of the time. With SETI off, it comes on maybe once per hour and only for a few minutes. Remember that Power = Heat

 

[m0ti]

They do consume a little bit more.

For example my computer (AXP 1600+@1900+) consumes 150W while idle. When crunching, it's at 165W. Yes, it's 10%, but if the computer's going to be on anyway, it certainly costs just marginally more for it to be doing something useful.

 

[Shaka]

Well, the voltage is the same, but the current drawn will vary with activity. Registers being rewritten, the ALU churning out results, etc.

What I'm kind of geting at is that when ppl say "use your CPU's idle cycles for something useful", it's actually costing more to do DC than it is to just let the computer idle.

EDIT: ahh just saw the replies. Well, since the power consumption isn't really too much greater, then I will install SETI on my dad's comp.

 

[titanmiller]

An extra 10W it only adds up to 50 cents per month more electricity (@ $.07/kWh)

 

[muttley]

ah, but talked about also is the constant temperature would prevent expansion and contraction by running a DC program.

(I'M BACK and am ready to find ET and kick some alien but!!!)
(actually I had a intestine bug, I'll spare the details.)

muttley

 

[CraigRT]

Originally posted by: titanmiller
An extra 10W it only adds up to 50 cents per month more electricity (@ $.07/kWh)

Thats what I was thinking.. I seriously would not worry about the extra power consumption...

 

[kadajawi]

I recall having tested my system... On full load its IIRC 20 to 30W more than idling. That was with a Celeron 366@458.

 

[Mark R]

I've tested a thunderbird athlon 1000 - and the system uses about 30W more when running SETI.

Cost of power for 1 month (essentialy running only the idle loop) I've estimated as £4/month (excl monitor). Running SETI would raise this to about £5.50/month.

The amount depends on the CPU model and speed, and the cost of electricity. Yes, you will pay a little extra for running background tasks.

If you look at the D.net RC5-64 project - you can estimate the amount of electricity used for the calculation:
Assuming P3-1000 MHz as the average CPU, which uses an additional 10W when running. Total electricity consumption is about 16300000 kWh (or about 12,000 tonnes of CO2).