Hi, On Mon, Nov 21, 2011 at 11:30:22PM +1100, Russell Coker wrote: > On Mon, 21 Nov 2011, Patrick Schoenfeld <schoenf...@debian.org> wrote: > > well, its obvious that the absolute power consumption, which is what > > you measure, has increased, given that the performance of the systems > > has increased as well. > > If you are setting up a network of machines for bitcoin mining then it's most > likely that modern systems would give the best value for money. > > > Measuring absolute values is all nice to compare the effective cost of > > running a system, but it does neither support nor weaken the point that > > modern systems are much better at power-saving. > > If you have tasks which require little CPU power (such as a DNS server) and > the system is idle most of the time then comparing the idle power use is the > most important thing.
Uhm.. yes, its the "most important thing" for you to decide weither the system is over-sized for a job that could eventually be very well be done by a atom system or even some low performance embedded system. However it does not qualify for a *general* assesment weither modern systems have become better at power-saving or, because its still not comparable. If you really do not need the extra power, you are still able to buy a modern but less powerful system, like lets say an Atom. You can compare that machines to draw a usefull assesment. > Another example is the Internet gateway system I use. It's a P3-800 and I > have no plans to upgrade it because it can handle higher speeds than my ADSL > link and that's all that is required. Same as above: Its not like you are forced to use a P3-800 or a even more over-sized system for that purpose. An atom might fit and will have less power consumption. > > Also to actually draw any conclusion from your statistics, one would > > need to know more about the hardware in question. Especially its unclear > > weither the PSUs used in the systems all have the same efficency. > > Whether the PSUs are of the same efficiency doesn't matter much as the > options > for switching them are limited. No, the options for switching them are totally unrelated to a comparison of the absolut power consumption. > In the unlikely event that the P3 class > desktop PCs I tested gave better results than Pentium-D and other newer > systems because of having better PSUs it wouldn't matter as the newer systems > need SATA connectors and an extra 4 pins on the motherboard connector. The point is not weither you can change the PSU of a P3 with the PSU of an Pentium-D or newer. The point is weither a Pentium D with a better Pentium D-suitable PSU would have given different results. (or same vice versa) Because, today you can chose between PSUs which (usually) vary between 70% and 90% efficiency. Dunno what efficiency previous PSUs had. So if your P3 might happen to have a PSU with an efficiency of 90%, while your Pentium-D has an efficiency of 70%, this *will* result in a significant difference in comparibility of the two values. > But I don't expect that PSUs have become less efficient, if anything I would > expect them to have improved slightly in recent times. Maybe a P3 system > would use even less power if it had a PSU taken from a newer system such as a > Pentium-D. Well, while that is your expectation, you did not back it with facts and therefore we need to assume that this expectation is false. -Patrick -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111121132012.GB10017@debian
