DDC said:
I would like to know if the usb shown here is faster than a ide drive.
http://www.kasercorp.com/showbig.asp?id=45
It is about 40% as fast as a typical IDE or SATA hard drive.
The use that i would like to do is putting the page file of windows
into that thing we all kknow that usa 2 drive can performe to 400mb/s
400 mb/s = 400 millibytes/s, which is about equivalent to typing
5 words per minute.
Correct capitalization of units is very important.
M = mega
m = milli
b = bit
B = Byte
The USB2 *interface* can do 400 Mb/s, or 50 MB/s.
That does not mean a device - including hard drives - attached to
a USB2 port can to that much:
1.) The device might not be capable of putting that data onto
the USB bus at that rate.
2.) USB requires a *lot* of CPU overhead. If the CPU is busy
with other things, USB throughput can be cut dramatically.
Conversely, if the CPU is spending a lot of time managing USB
traffic, performance on other tasks can suffer.
3.) USB data transfers are packetized and the packet headers add
significantly to the amount of data being transferred. And that
packet overhead eats up some of that 400 Mb/s.
USB drives are a *terrible* place for page files. When your CPU
needs to do paging, it usually has much better things to spend
CPU cycles on than managing the USB bus. Hard drive I/O on a
system with a contemporary desktop CPU can easily use up half CPU
cycles for a USB hard drive, versus 5% to 8% for an IDE or SATA
drive.
If you want a decent external hard drive, go with SCSI, FireWire,
or external SATA (e-SATA). Highpoint makes a couple of SATA
cards that have e-SATA ports, and they also sell e-SATA hard
drive enclosures for you to stick either IDE or SATA drives into.
that i peaf performane but the average speed of the pen drive is
13mb/s in writing and 15mb/s in reading.
You mean 13 MB/s writing and 15 MB/s reading.
Pathetic compared to a hard drive.
Also i know that my primary drive goes around 50mbs
You definitely mean 50 MB/s. You might get that on the outer
cylinder of your drive, but your are probably getting only 70% of
that on the inner cylinders.
but i'm not sure
about the units. should it think that 13mb/s x 8 would give me a
104mbs in writing mode???
Sounds like you wanted to say 13 MB/s = 104 Mb/s
When comparing drive speeds, MB/s is usually used, not Mb/s.
