Slashdot Mirror
Swaying CPU Fans
Vindi submitted a New Scientist story about a CPU fan that flaps in the breeze. 2cm metal or polyester
fan blades, and use less power then a traditional rotary fan. They move less
air then the traditional fan, but for laptops, using 99% less power
can't hurt. Update Hey its a duplicate from saturday! Guess I shouldn't
post while planning my trek to see LotR tomorrow. Go ahead, flame on.
Look for the most insightful posts from the original article and whore all you want:
0 22 9&mode=flat
http://slashdot.org/article.pl?sid=01/12/13/201
I've been looking into this a lot recently, and there's some pretty (ahem) cool developments on the cpu front recently, with x86 architectures.
.13u means a lot. Frequencies are so high and chips are so powerful that underclocking has become a real option. A good general target for fanless operation is about 12 watts. You can go higher with good case airflow, or lower if you're dealing with troublesome ambient temperatures.
Some people point to the VIA C3-800, but if you have real computing needs, steer clear. It runs comparable to a Celeron 400, which is almost, but not quite adequate for general computing. Instead, check out the old reliable suppliers. The shift to
Right now, you can take the Intel Tualatin pIII 1.13GHz (28W), cut the bus speed to around 100MHz, cut the voltage down to about 1.1v and be right in the target range. Of course you won't know exactly w/o experimentation on your cpu, but it *should* be doable. If you're worried about losing efficiency to bus speed, remember that you can compensate by running it on one of the PIII DDR chipsets that are now available (upping effective bus speeds to 200MHz) or waiting until February, when Intel says they'll release a similar part themselves. Additionally, the 512k (vs 256k) cache on the pIII-s will offset lower bus speeds. Just check out the specs of the PIII-M LV models at developer.intel.com and ask how they got to those low wattage numbers with the same core. Since the last fanless G4 was 400MHz and claimed (in its wildest fantasies) to be a supercomputer twice as fast as a pIII, a fanless 800MHz pIII is not insignificant.
Even better, surprise, is AMD. The current mobile palomino runs at 1.1GHz, 1.1v, 25w. This is clearly just an underclock of the current 1.75v desktop XPs. But what it tells you is that the AMD architecture is very open to undervoltage at lower clock speeds.
Now if you consider AMD's forthcoming die shrink, things really look good. Zdnet.de reported (unsourced) that the Athlon 1.73GHz processor would drop from about 75W to 45W after the changeover. Depending on how far you could drop the voltage, you could be looking at a 1-1.2GHz part running at about 10W! Fanless! Now imagine (a beo..no) 2 of these in a well ventilated case, with an MPX board -- 2GHz of dead silent AMD power! Wooo!
that we create a beowulf cluster of repeated Slashdot stories.
No statement is true, not even this one.
At least from Piezo Systems Inc. [piezo.com] in Cambridge, MA. Their specs are worth reproducing:
* Input Voltage: 115VAC, 60 Hz
* Capacitance: 15 nF
* Power Consumption: 30 mW
* Volume Flow Rate: 2 CFM, (0.9 l/s)
* Peak Air Velocity: 400 FPM, (2.0 m/s)
* Weight: 2.8 grams
* Mounting: #2-56 clr. holes, 2 places
* Temperature Range: -20 C to 70 C
* EMI/RFI: None
However, they're not cheap. Pricing starts at $149. Additionally there is a Piezoelectric Resonant Blade Element [piezo.com]. Interesting stuff. Hopefully mass production of piezoelectric fans will lower their price to the average customer range.
...somehow use the heat from the CPU to power the fan. As the CPU got hotter, the fan would move faster.
I have no idea how this could be done, but there must be a way.
It is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail. - Abraham Maslow
Fans may have evolved to the point where they don't have to keep going around in circles, but Slashdot hasn't.
Aw, screw it. In the spirit of the season, I'll just wish them both a Merry CowboyNealmas!
Mr. Ska
This means that searches for things like "IBM" or "cpu" or "CSS", etc end up with no results. This makes it much more difficult to find things like duplicate stories about AMD CPU. etc
this likely needs to be fixed so that when an editor searches for a dupe he does not get trapped.
"It is a greater offense to steal men's labor, than their clothes"
It's kind of hard to tell exactly what this article is describing, but it sounds like exactly the same thing at half the size.
--
"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
For those who are unaware, piezoelectric crystals are items that will change shape under the application of an electric field and/or generate a potential difference (i.e. a voltage) when squeezed.
They're used in inkjet printers - they're in ink some cartridge when an electric field is applied to them and they change shape, forcing the ink out of the I also hear the they used them in the ipod for some sort of playlist control mechanism.
words of less than 3 characters are not indexed
/. articles.
This means that searches for things like "IBM" or "cpu" or "CSS", etc end up with no results.
No, it would mean 'is' and 'it' aren't indexed. Since the page actually says less than 4, your second statement is true though - which is wierd considering the number of TLAs in
"don't fall into the fallacy of believing that Perl can solve social problems. Maybe Perl 6 can, but that's a ways off"
The chance of a fire is very low indeed.
True....very true.
Unless of course, you're an AMD owner (while I am an AMD supporter, this kinda worries me).
I'm sure we all remember article. Take a look at the results.
Like sex? Read and write about it! Indecent Blogging
It's been a while since I pondered the intricacies of slashcode, but they could probably filter it so that it caught TLAs which were uppercased (well, any three-letter word which was uppercased, it wouldn't know it was an acronym). This would catch stuff like IBM and CSS, since those are the kinds of things people would like to be able to search on.
Communication is only possible between equals
What I want to know is just what the people in this industry did to CmdrTaco that would make him Slashdot their servers twice in a week?
sarchasm: The gulf between the author of sarcastic wit and the person who doesn't get it.
So I wouldn't want a box designed for natural convection only. But for the user that finds adding a USB peripheral challenging, doesn't need 1GHz, and doesn't want that fan humming, maybe it would work.
It's been done, by apple (who else?). Since the introduction of the models that had slot-loading CD drives in October 1999, iMacs have been fanless, cooled totally by convection currents. Not surprisingly, the iMac was designed for the novice user who doesn't need 1GHz and won't ever be dinking around in the thing's innards, so convection cooling was the way to go.
The G4 Cube was also cooled in this manner, but that model was directed at studio managers and CEO types who likewise wouldn't need expandability.
~Philly
Hey its a duplicate from saturday! Guess I shouldn't post while planning my trek to see LotR tomorrow.
Perhaps you shouldn't check spelling and capitalization while planning your treks. Do your planning BEFORE you spellcheck.
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.