Fan noise


Published on

Are you really bound to hear fan noise when operating a PC? Not by principle. Can an energy efficiency be allocated to the activity of a computer? Not by principle, but the energy consumption can be reduced. What does one of these have to do with the other? Perhaps more than you expect!

Published in: Technology, Business
  • Be the first to comment

  • Be the first to like this

Fan noise

  1. 1. »Energy efficiency«in data processing?Stefan FassbinderDeutsches KupferinstitutAm Bonneshof 5D-40474 DüsseldorfTel.: +49 211 4796-323Fax: +49 211
  2. 2. The German Copper Institute, DKI, isthe central information and advisoryservice dealing with all uses of copperand copper alloys.We offer our services to: Commercial companies We can be contacted by: The skilled trades  post Industry  phone R & D institutes  fax Universities  e-mail Artists and craftsmen  internet Students  online database, or Private individuals  personally
  3. 3. An accidental finding:Wanted:The noise free living room PCFound:An energy glutton wasting energy forlack of aluminium and copper
  4. 4. This brand new PC power supply unit at 39.95€ promises to be 60% less noisy! 4
  5. 5. Well, 60% less noiseis at least a statement!Though not really any more than that …… as long as the question remainsunanswered:Less than what?
  6. 6. This was not the wayNow what to do?Loss heat can be• either blown away• or avoided!So a different solution had to be found:A fanless PSU (at 79.50€) workstotally noise free!
  7. 7. How is this reduction innoise level achieved?By improvement of passive cooling or byreduction of cooling need, say losses?By improvement of passive cooling and byreduction of losses:• Substantial enhancement of cooling surface on the aluminium heat sinks• Substantial enhancement of copper cross sections in the windings of HF converters
  8. 8. But loss reduction holdsthe greater share!140W  Starting up a PC with120W subsequent idle operation P100W80W60W40W Original PSU Antec True 380 SP20W Fanless PSU FSP ZEN (2009) 0W 00:00min 05:00min t  10:00min
  9. 9. How to reduce losses? – Use more material!Conventional Fanless420 W 300 W
  10. 10. Still, the actual net powerconsumption of a common PC(built in 2005, 800 MHz) is:• 50 W when idling (whereas writing a text or composing an Excel table is idle for a PC!),• 100 W at peak processor demand (gaming),while the common power supply unit is verymuch over-dimensioned!
  11. 11. Therefore the 300 W modelcan quite convenientlyreplace a 420 W unit. PC power Antec FSP ZEN True 380 with active supply unit SP with PFC, comparison active fanless Power rating 380W 300W Weight 1995g 2223g Material intensity 5.250g/W 7.410g/W Factor 100% 141%If this were not so the copper content wouldhave to be 41% higher rather than just 11%
  12. 12. Who else should have aninterest in this topic?This is the reply to a request to thecolleagues from sentMarch 31, 2009:I‘m still waiting…
  13. 13. Conventional PC powerunit, 420W PC power supply LC4620, S/N: 7J090402 Rated power 420W Input 30.0A 28.0A 14.0A Output P 3.3V 5.0V 12.0V P P /P N η 4.4W 0.0A 0.0A 0.0A 0.0W 0.0% 0.0% 13.5W 0.0A 0.0A 0.0A 0.0W 0.0% 0.0% 64.0W 0.0A 0.0A 3.3A 40.1W 9.5% 62.6% 71.0W 17.5A 0.0A 0.0A 57.8W 13.8% 81.3% 109.0W 0.0A 0.0A 6.7A 80.2W 19.1% 73.5% 148.0W 0.0A 0.0A 9.4A 113.2W 26.9% 76.5% 161.0W 0.0A 25.0A 0.0A 125.0W 29.8% 77.6% 286.0W 0.0A 0.0A 18.8A 226.0W 53.8% 79.0% 307.0W 28.5A 24.0A 0.0A 214.1W 51.0% 69.7% 450.0W 28.5A 25.0A 7.0A 303.1W 72.2% 67.3% 740.0W PSU failure after ≈2s with <20% overload
  14. 14. Conventional PC powerunit, 300W PC power supply T.I.P. 300 ATX Rated power 218W Input 14.0A 20.0A 6.0A Output P 3.3V 5.0V 12.0V P P /P N η 0.0W 0.0A 0.0A 0.0A 0.0W 0.0% 0.0% 3.1W 0.0A 0.0A 0.0A 0.0W 0.0% 0.0% 21.4W 0.0A 0.0A 0.5A 6.1W 2.8% 28.6% 43.3W 0.0A 2.2A 0.9A 21.7W 9.9% 50.0% 56.8W 0.0A 0.0A 3.2A 38.9W 17.8% 68.5% 70.0W 0.0A 0.0A 4.3A 51.4W 23.5% 73.4% 97.0W 0.0A 5.0A 3.4A 66.1W 30.3% 68.1% 122.0W 0.0A 5.0A 5.2A 87.2W 40.0% 71.5% 148.0W 5.8A 5.0A 5.2A 106.0W 48.6% 71.6% 181.0W 5.8A 9.5A 5.2A 129.0W 59.1% 71.3% 226.0W 14.0A 9.5A 5.3A 157.4W 72.1% 69.7% Shut-off – no more measurements possible
  15. 15. Conventional PC powerunit, 380W PC power supply Antec True 380 SP Rated power 380W Input 28.0A 35.0A 18.0A Output P 3.3V 5.0V 12.0V P P /P N η 0.0W 0.0A 0.0A 0.0A 0.0W 0.0% 0.0% 4.4W Fanless PC power 0.0A 0.0A 0.0A 0.0W 0.0% 0.0% 28.3W 2.2A 0.0A 0.0A 7.1W 1.9% 25.1% 64.8W unit, 300W 2.5A 0.0A 0.9A 19.1W 5.0% 29.4% 90.0W 2.5A 4.0A 0.9A 39.1W 10.3% 43.4% 109.0W 148.0W Rated efficiency: 6.1A 6.1A 4.4A 4.6A 0.9A 3.3A 53.3W 82.6W 14.0% 21.7% 48.9% 55.8% 174.0W 5.6A 9.3A 3.3A 105.0W 27.6% 60.3% 282.0W 89% (at full load) 27.0A 9.3A 3.4A 176.2W 46.4% 62.5% 381.0W 27.0A 17.0A 6.7A 254.5W 67.0% 66.8% 463.0W 27.0A 17.0A 12.9A 328.9W 86.6% 71.0% 561.0W 27.0A 17.0A 19.0A 402.1W 105.8% 71.7%
  16. 16. How high is the »efficiency« of a PC?Much higher than earlier, anyway!Ancient XT: Latest model:f = 4,7 MHz f = 4,7 GHzPel ≈ 40 W Pel <<400 WThis looks like an efficiency improvement by farmore than a factor of 100! With similar values for• storage units,• hard disks,• graphic adaptorsyou end up with improvement factors around 106!
  17. 17. Where will the journeystill take us?A limit will be reached only when for one data bitonly more one electron needs to be moved.So long, however, it‘s still 10,000 to 100,000electrons that need to be employed for the smallestoccurring »elementary process« in data processing.So the theoretical potential• with miniaturisation,• with acceleration of procedures,• with reduction of energy demandstill lies somewhere near a factor of 104 … 105!
  18. 18. Hence the major partof the job is done• The first computer »Zuse Z1« had the dimensions of an electrical locomotive…• …along with its power consumption…• …and this with the performance of a credit card sized pocket calculator which you get as a giveaway nowadays and which is supplied from 2 cm² of solar cells or with a button cell battery for no less than a year!
  19. 19. But progress withprocessors is continuing: PC built upgraded 2005 2011Processor 2.6 GHz, 2*2.7 GHz,RAM 512 MB, 4 GB, 400 MHz 1.6 GHzIdle power 59 W 45 Wmeasured with the same fanless PSU
  20. 20. Only what‘s the use of it allif you do anything you canthink of in order to e. g. implement allavailable efficiency techniques in amodern diesel engine and then add agearbox with 30% of losses?Nobody would do that in a car –in a PC it‘s the usual approach!For the PSU is sort of a»gearbox for electricity«.
  21. 21. The noiseless operationcomes for free! Calculation of power consumption costs for a PC (built in 2005) before and after replacing the conventional PSU with a fanless one Conventional PSU with fan Fanless PSU Output values P S Q LF cosφ P S Q LF cosφFull load 100h/a 135.5W 138.9VA 51.4var 0.975 0.977 113.0W 123.2VA 67.0var 0.890 0.940No load 3000h/a 82.0W 87.1VA 29.3var 0.939 0.945 59.2W 70.5VA 38.1var 0.843 0.886»off« 5660h/a 6.3W 24.5VA 23.6var 0.256 0.307 2.0W 24.1VA 24.0var 0.080 0.112 PSU 39.95 € 79.50 €Price Power 14.0c/kWhConsumption 294.91kWh/a 200.36kWh/aElectricity costs 41.29€/a 28.05€/aPayback time 2.99aThe saved losses pay back for the pricepremium within 3 years. The global savingspotential in 1 bn PCs would be 100 TWh/a!Morals: I am a fan of the fanless design!
  22. 22. Then why do portable PCs provide the same computing performance with that much less electricity?This notebook PCis equipped with an integrated55 Wh battery and an additional95 Wh battery and runs for about13 hours on these, corresponding to12 W net DC power requirement!
  23. 23. Metering conditions:• WLAN off,• no UMTS device,• no »action games«,• moderate screen brightness.Whereas it is remarkable with the laptop PC• that the screen is already included• and the whole PC uses less power …
  24. 24. … than a desktop flat screen uses for itself alone!
  25. 25. So in the end there is onequestion remaining open:Why can this technique not be builtinto a desktop PC?Energy is still way too cheap.The availability of electricity from theaccumulator is a reason to saveenergy – the electricity price obviouslyis not.