Hi Tammy, I am also in the market for an external drive, and have found some things you should look out for when shopping for these monsters.
First is to look at what kind of interface it has. USB is the common one, but some models will also come equipped with a Firewire cable, and even some will come with an RJ45 jack, which means it can be connected to the network and used as a network drive. Secondly, you'll want to look at the rotation speeds of the disk, sometimes measured in RPM's. The standard is 7200 rpm's. Anything below that is tantamount to very slow access. Thirdly, and I think this is most important, is the read/write speeds and the transfer speeds, usually measured in megabytes per second. There is really no standard for this, and some retailers will sometimes try to fool you into thinking that the higher the transfer speed, the faster you'll get data on the drive. While this can sometimes be true, the fact is that the read and write speed is more important than the transfer speed, as the transfer will have to wait while the data is being read or written. The transfer speed may be referring to the transfer rate of the cable or connection, and not necessarily the drive itself. One drive I found was boasting a transfer speed of 480 mbps, but the read/write speed was abyssmally slow. An example I can cite is a electronics' chain here in Toronto called Future Shop. They were selling a 500 Gb external hard drive for 99 dollars. Once I saw that, my mouth fell open, as I couldn't believe the price, until I saw the read and write speeds, about 27 and 25 mbps, reading and writing, respectively. While this seems high, try to remember that the mbps stands for megabits per second, not to be confused with megabytes per second, as most people commonly see it as. What shocked me was the fact that it still said an rpm of 7200, which should not support that kind of read write speed, but then I realized what might be slowing the read write speeds up, and that leads me into the last point I want to make. Circuitry... You can have the most expensive hard drive in there, but if the enclosure stinks to high heaven, then that really expensive drive means absolutely nothing. The circuitry must come with a cache of some kind, and some kind of power switch, as this will control how long the hard drive lasts. Continuously keeping the drive on will shorten the lifespan of the drive. Although it has not been proven to shorten it's lifespan dramatically, it does shorten it nonetheless. So this is what I think you should look out for, and I hope this helps in some way. Victor Visit the JAWS Users List home page at: http://www.jaws-users.com Address for the list archives: http://www.mail-archive.com/[email protected]/ To post to this group, send email to [email protected] To unsubscribe from this group, send an email to [EMAIL PROTECTED] For help from Mailman with your account Put the word help in the subject or body of a blank message to: [EMAIL PROTECTED] Use the following form in order to contact the management team http://www.jaws-users.com/BlindComputing.php If you wish to join the JAWS Users List send a blank email to the following address: [EMAIL PROTECTED]
