On 5/5/05, John A. Dundas III <dundas at caltech.edu> wrote: No. TTBOMK, the tecnological progression went: Generation 1: ST-506 G2: RLL (which was just ST-506 with different encoding giving about 25% greater capacity; drives *could* be exchanged but weren't rated or guaranteed at the higher capacity and might work, might not, or might work for a while then fail) G3: ESDI (higher capacities, greater transfer rates, slightly more intelligence on the drive and less in the controller) G4: IDE (all controller logic is embedden in the drive, which attaches straight onto the PC ISA AT bus, thus the name AT Attachment or ATA; first change of cabling, from one shared control cable for each pair of drives plus two data cables) (Next came the ATA Packet Interface, allowing non-HD devices to be attached, primarily optical drives - CD-ROMs etc. - but also Zip & Jaz type removable drives, tape drives and so on) G5: EIDE (unsure of the exact technical difference, but I think it's the addition of Logical Block Addressing - LBA - in place of simple Cylinder:Head:Sector (CHS) addressing) G6: UltraIDE (doubled the nunber of conductors in the cable to 80 to reduce crosstalk, allowing doubling of the transfer speed to 16Mb/sec; AKA UltraDMA and other names) G7: UltraDMA/33 (another doubling) G8: UltraDMA/66 (and another) G9: UltraDMA/100 (running out of headroom now) G10: UltraDMA/133 G9: SATA, Serial ATA. Another change of cabling, to serial cables, one per drive; no more sharing, no more master/slave assignments or jumper settings. SATA 1 ran at a nominal 150Mb/s but initial drive mechanisms couldn't deliver data off disk that fast, so it was no faster than UltraDMA/133. However, now we're heading towards... G10: SATA2. I can't recall the speeds offhand but it's more than doubled, I think. Of course, in the same timeframe, SCSI has been doing its own thing, more than keeping pace overall. Then there's Fibre Channel, and in the olden days there was Xilinx and other systems... -- Liam Proven Home: http://welcome.to/liamsweb * Blog: http://lproven.livejournal.com AOL, Yahoo UK: liamproven * ICQ: 73187508 * MSN: lproven at hotmail.com