Hi, On Tue, 12 Oct 2010, Adam Nielsen wrote:
>>> Not sure if it's still the case, but these drives used to have smaller >>> platters to reduce the seek time, so they were pretty much 2.5" drives >>> in a 3.5" shell. >> >> Impossible. > > Well a quick Google suggests otherwise: > > http://www.pcguide.com/ref/hdd/op/mediaSize-c.html (see table at end of > page) > > And to quote from the end of > http://www.datarecoverylink.com/understanding_platter_sizes.html: > > "Decreasing the size of the platters decreases the distance in which the > head actuator must move the heads side-to-side performing random seeks > thus improving seek time and making random reads/writes more > efficient...The movement to smaller platters began in earnest when some > manufacturers "trimmed" the platters in their 10,000 RPM hard disk > drives from 3.74" down to 3" while keeping them as standard 3.5" form > factor drives on the outside for compatibility. Seagate's Cheetah X15 > 15,000 RPM drive goes even further, dropping the platter size down to > 2.5", again trading performance for capacity" > >>> So given equal RPM the 2.5" drive should have a faster full-stroke seek, >>> but as has been pointed out, an SSD would be even better in this respect. >> >> How do you see an effort of 2.5" against 3.5"? > > Well if the platters are smaller the heads have less distance to move, > so seeking from the start of the disk to the end would be quicker... > >> The opposite is fact. >> >>> [1] >>> http://www.latestpcnews.com/western-digital-launches-new-backplane-compatible-wdvelociraptor-hard-drive/ >> >> Only advertising, sorry. > > Not all advertising is wrong :-) All these aspects forget the capacity loss. I was talking about "same capacity". Viele Gruesse Eberhard Moenkeberg ([email protected], [email protected]) -- Eberhard Moenkeberg Arbeitsgruppe IT-Infrastruktur E-Mail: [email protected] Tel.: +49 (0)551 201-1551 ------------------------------------------------------------------------- Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH Goettingen (GWDG) Am Fassberg 11, 37077 Goettingen URL: http://www.gwdg.de E-Mail: [email protected] Tel.: +49 (0)551 201-1510 Fax: +49 (0)551 201-2150 Geschaeftsfuehrer: Prof. Dr. Oswald Haan und Dr. Paul Suren Aufsichtsratsvorsitzender: Dipl.-Kfm. Markus Hoppe Sitz der Gesellschaft: Goettingen Registergericht: Goettingen Handelsregister-Nr. B 598 ------------------------------------------------------------------------- _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
