jimrx4 said:
I have what's probably an amateurish question. I've been looking
over the specs of an external SATA drive (eSATA). It says it can
connect either to an eSATA port or can use a USB 2.0 input. The
eSATA is rated at 3 Gbps and the USB is at 480 Mbps. Which is
theoretically faster? Does it make a difference? Why am I asking:
What's the difference between gigaBITS per second verses megabytes
per second?
Google...
Examples...
A search for:
What is Gbps
http://www.google.com/search?hl=en&q=what+is+Gbps
Gives you:
http://www.webopedia.com/TERM/g/Gbps.html
Which tells you:
"When spelled Gbps, short for Gigabits per second, a data transfer speed
measurement for high-speed networks such as Gigabit Ethernet. When used to
describe data transfer rates, a gigabit equals 1,000,000,000 bits."
1,000,000,000 bits per second transferred. Think of bits as anything easy
for you to comprehend to put it into perspective. For example - can you
imagine 1,000,000,000 (That's one billion) cars passing through an
intersection in one second?
A search for:
What is Mbps
http://www.google.com/search?hl=en&q=what+is+Mbps
Gives you:
http://www.webopedia.com/TERM/M/Mbps.html
Which tells you:
"When spelled Mbps, short for megabits per second, a measure of data
transfer speed (a megabit is equal to one million bits). Network
transmissions, for example, are generally measured in Mbps."
1,000,000 bits per second transferred. Think of bits as anything easy for
you to comprehend to put it into perspective. For example - can you imagine
1,000,000 (That's one million) cars passing through an intersection in one
second?
Where I think you are confused:
You asked in the end, "What's the difference between gigaBITS per second
verses megabytes per second?" when it has nothing to do wth what you have
given. You are quoted as saying, "... eSATA is rated at 3 Gbps and the USB
is at 480 Mbps ..." and since you capitalized the first letter of each
abbreviation (Gbps and Mbps) - you meant gigabits-per-second and
megabits-per-second - not megabytes. You are comparing apples to apples but
seem to think you are comparing apples to oranges...
Check out this web page:
http://en.wikipedia.org/wiki/Data_rate_units
That will give you both Megabits and Megabytes for speed measurements so you
can better understand.
Theoreticals:
-- USB 1.0 - 1.5 Mbits/sec
-- USB 1.1 - 12 Mbits/sec
-- USB 2.0 - 480 Mbits/sec
-- USB 3.0 - 4.8 Gbits/sec (unreleased)
-- 1394a - 400 Mbits/sec
-- 1394b - 800 Mbits/sec
-- ATA - 3.3 to 133 Mbytes/sec
(Depending on version between ATA-1 and ATA-7,
not including Serial ATA - SATA)
-- SATA - 1.5 Gbits/sec
-- SATA II - 3.0 Gbits/sec
-- eSATA - 1.5 to 3.0 Gbits/sec
So - depending on your need (do you need the speed, the space, both? how
much are you willing to spend?) - you can choose whatever you want with the
above information at your fingertips... (And Google. And
http://www.pricewatch.com/. *grin*)
