Quote:Original post by MichalsonNoted computer scientist David Manning from Ridgefield University has said that the Playstation 3 is the most powerful computer he's ever seen.

LOL!!! I had to search the name to get it, but that is hilarious!

Quote:Original post by smart_idiot
Out of curiosity, how does information processing work in terms of energy efficiency?

True, there is tons of waste heat, but if you were using a computer as a replacement for a heater and all that heat was the desired outcome, is the processing that gets done in the process essentially free, and if not, what did the heat we should have gotten instead become?

Well, if you have blank hard drive, and write results of computation to it, some very very small energy comes into magnetic field. Rest just becomes heat, thanks to conservation of energy.
That's said, if a bit of information is irreversibly 'destroyed', some energy (log(2)*k*T or something like that) must be released as heat. The computation in which no bits are irreversibly lost may theoretically run absolutely 'for free' not even releasing any heat.

Also, it is in theory possible (but not always practically viable) to either a: heat your room directly without inefficiency of steam turbines or other means of electrical generation (more efficient than having power plant that powers your computer). or b: use heat pump that are more efficient than just heater (most heat pumps won't work when it's -30c outside tho).

I think no matter what distributed computing over the internet will always be cheaper then giant local clusters. For a few reasons.

1) I and the many other contributors to the project power our own respective node of the cluster. This means of course that I bear the cost of powering my node, not the project.

2) By having many nodes distributed over the world they (seti@home et al) do not have to provide cooling, further cutting their own energy costs down.

3) The cost to add additional nodes to their systems is marginal (mostly bandwidth costs), potentially additional servers to handle additional load.

So even if they could theoretically build a massive super computer for a marginal (marginal being relative to the cost of larger scale supercomputers), a distributed model still has many benefits over a large local cluster.

That and even if it were a bunch of marketing BS, I'd still contribute my hardware to the cause, at the very worst, my ps3 wastes some clock cycles contributing to a worthwile cause, which isn't to disimilar from not contributing, where my ps3 wastes some clock cycles contributing to some not so worthy causes, like entertaining me.