Power Consumptions

[rbutcher]

This topic of power consumption is one that bothers me now every time I get my electricity bill. DC started out as a fun hobby that allowed me to assemble secondhand parts people give me, together with the occasional new bargain I pick up (like semprons a while back), and crunch the world's problems away.
But I estimate I'm burning 100 watts per box, which defeats the object of climate prediction @ home.
Am I correct in assuming that the most power-efficient way to crunch is to buy the fastest AMD single core I can find, and run it as my sole box, storing working files on a USB stick and allowing the hd to spin down, and give away all the other boxes ?
How much juice does a hd use anyway ?

[Thor]

Well, an HD is pretty much nothig in terms of power consumption. I think it is save to say (and I have read it often) that it uses around 10W

I think a dualcore (AMD) with a very efficent PSU might be the better choice... It does not take a lot more power than a single core and still less than an Intel.

Take the smallest graphics card (or better none) you can find and leave the HD in... makes less trouble. And don't forget that Flash memory is supposed to have only very limited write cycles..

Thor

[rbutcher]

Thanks Thor.. prices in my area indicate that lower end of dual core AMD processors are the best bang for buck (athlon 64 X2 3800), assuming that :-
1. Clock speed - is this main criterion ? i.e. is a 2.2 ghz cpu going to do 10% more work than a 2 ghz cpu ?
2. Dual Core - does this double the work throughput, i.e. is a 2ghz dual-core going to do twice the work of a 2 ghz single core ? Or do programs have to be optimised ?
3. The dual core X2 3800 cpu uses only 89 watts according the the AMD website. Tom's Hardware figures are 217 watts at 100%, 129 at idle. So no great electricity saving here over my old single core XP 3000.
thanks
Rod

[Scoofy12]

1. if power is a primary concern, then you want lower clock speed. Power (and therefore heat) scale with (IIRC) the square of frequency. so lower frequency processors are more power efficient.
2. dual core processors don't take much more power than single cores, so that's more power-efficient as well. you won't get quite 2x the performance (depending on how memory-bandwidth bound your applications are... this is actually not so bad with AMD duallies), but if you run 2 instances of your DC app of choice (or 2 different ones), youll be close.
3. no great saving, but you will get nearly twice the work. and AMD's power management (cool n quiet?) works pretty well.