On Aug 21, 6:33 pm, Eric Herbert wrote: > You can only go as fast as the drive can read or write, whichever > drive is slower. 3Gb/s is the maximum transfer rate the interface > is capable of. Translates out to roughly 300MB/s. The fastest hard > drives on the market are only capable of reading at around 80MB/s > and writing at around 65MB/s sustained transfer.
not quite. the difference between HD speed and interface speed has been discussed on these lists many times. as eric correctly points out, the SATA-II interface is capable of handling 3 GB/s. but, new HDs themselves currently have sustained read/write speeds of around 120 MB/s or above. i have tested several using HDST that were in the 120 MB/s range (seagate and maxtor). i have not purchased the latest or most expensive HDs, so i assume that there are probably others out there that may be a bit faster. i have also tested PATA drives that were in the 100 MB/s range (seagate). this number has increased steadily over the past 20 years from less than 5 MB/s to the current level, and presumably will continue to increase. the best SSDs currently advertise read/write speeds of 275/250 MB/s. however, SSDs have a more limited number of read/write cycles before they fail compared to a traditional spinning platter HD, so i would NOT recommend getting an SSD to use as the boot drive. it will wear out in a few years of normal use. in any case, for the SATA-II interface to actually get to 3 GB/s would require two dozen or more of the latest HDs in a RAID, so in practice, it is unachievable. in reality, a new PATA drive is likely just as fast as a SATA-II drive, if it's the only HD on the bus. On Aug 21, 9:50 pm, Chance Reecher wrote: > Perhaps its a PCI thing? and NO, it is not a "PCI thing." if you bother to actually think about it, it should be obvious to anyone who's mastered sixth-grade arithmetic. multiply the bus speed (MHz = million cycles/s) times the bus width (bits/cycle) and divide by 8 (bits/byte) and you will find that the PCI bus in an old Mac 9600 with a bus speed of 50 MHz is still way faster than the latest HDs. (50,000,000 cycles/s) x (32 bits/cycle) x (1 byte/8 bits) = 200,000,000 bytes/s = 200 MB/s. in practice it will be a bit less, but still faster than any one single HD. -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
