`Hi!> > let me give you a real world example then, and the numbers I'm using are> > ballpark the same as you'll find in a (mobile) core 2 duo datasheet, I> > just rounded them a little so that the math works out nice.> > > > power at full speed: 34W> > power at half speed: 24W> > power at idle: 1W> > I have usually seen different numbers, for example:> > http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/30430.pdfTrust Arjan, modern cpus work as he describes.> Although this paper speaks about thermal design power instead of power> consumption, i suppose that it should be roughly equal.> > For example Athlon 64 3700 (ADA3700AEP5AR):> > 2.4 GHz, 1.5 V -> 89 W> 2.2 GHz, 1.4 V -> 72 W> 2.0 GHz, 1.3 V -> 53 W> 1.8 GHz, 1.2 V -> 39 W> 1.0 GHz, 1.1 V -> 22 WI guess that means athlon 64 is 'old'.> Even my measurement on PC (Athlon X2, VIA K8T890) of complete PC power> consumption shows that it is more efficient to be busy for 2 time units> on 1 GHz than be busy for 1 time unit and be idle for 1 time unit> on 2 GHz.> > 1 GHz:> both cores idle:	48 W> one core busy:		57 W> two cores busy:		66 W2 sec decoding video at both cores: 132J> 2 GHz:> both cores idle:	54 W> one core busy:		78 W> two cores busy:		95 W1 sec decode @ 2GHz + 1 sec idle @ 1GHz: 143JSo even on your hw difference is not too big... and take a look atnumbers from core2duo.Actually...4 sec decode @ 1 core @ 1GHz: 57*4=228J1 sec decode @ 2 cores @ 2GHz, then idle: 95 + 48*3 = 142+95 = 235J...Ok, so it is still 	 win, but even smaller one..							Pavel-- (english) http://www.livejournal.com/~pavelmachek(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html-To unsubscribe from this list: send the line "unsubscribe linux-kernel" inthe body of a message to majordomo@vger.kernel.orgMore majordomo info at  http://vger.kernel.org/majordomo-info.htmlPlease read the FAQ at  http://www.tux.org/lkml/`