External hard drive speeds

[PsyMan]

Now, am I getting my megabytes per second and megabits per second fuddled here?

If I have a SATA hard drive in an external caddy connected via firewire800 or USB 2.0 will it make a scrap of difference?

firewire800 = 800 mb/s
USB 2.0 = 480 mb/s
SATA Drive = 150 mb/s

thus am I right in deducing that with either I will still only get 150 mb/s

???

Yours truely, confused from the UK

[BCSchnei]

Most Serial ATA drives have an external max transfer rate of 150 Mbytes per second.

The speed of USB and Fireware are measured in Mbits per second.

8 Mbits = 1 Mbyte

So if you do the math:

nn Mbytes times 8 = rate in Mbits

150 x 8 = 1200

So the max transfer rate of a SATA drive is 1200 Mbits per second.

SATA drives are much faster and getting faster then either USB 2.0 or Firewire.

-BCS

[Rich]

Hard drives are measured in Megabyte/sec (MB/s) ATA133 is therefor 133 Mb/s and SATA is 150 MB/s. To convert from megabits to megabytes (1 megabit=0.125 Megabytes) Therfore

Firewire (100, 200, 400, 800 Mb/s speeds)= (12.5, 25, 50, 100 MB/s) so to get near the SATA of 150 MB/s, you would need to have a device and controller that is operating at 1200 mb/s. The IEEE standard does go up that far and it may soon include 1600 and 3200 Mb/s, but I think these are more of future standards.

USB 2.0 = 480 Mb/s = 60 MB/s

So, if you connect the SATA drive by way of USB 2.0, you are getting speeds a bit below are an PATA 66 hard drive. If you are using firewire, unless you have a 1200 mb/s connection, you probably should have just bought an ATA 100 hard drive since you are probably getting 100 MB/s. That is my take on the transfer rates. Obviously, no rate is absolute and varies due to job.

[Blinkin]

i've actually been looking everywhere for a external hdd that connects via firewire. so uh, where can i find it online?

[Rich]

Try Newegg

http://www.newegg.com/app/ViewProductDesc.asp?description=17-146-187&depa=0