[ubuntu-uk] fast external hard drive

[Alan Pope]

On Wed, Nov 01, 2006 at 02:44:43PM +0000, ajb35 at kent.ac.uk wrote:
> I'm running my desktop computer completely off a USB hard drive with no problems. As long as you have a USB2.0 port and drive then the maximum transfer rate is 480MBPs. When you consider a standard PATA connection is only 133MBPs it's more than enough. Firewire connections are also faster then hard drives can throughput so you should have no problems with a firewire or USB2 HDD.
> 

Careful, you're mixing bits and bytes there.

USB2 has a theoretical maximum of 480Mb/s (that's 480 mega bits per second)
PATA has a theoretical maximum of 133MB/s (that's 133 mega bytes per second)

480 (bits) / 8 (bits per byte) = 60

Therefore USB2 has a theoretical maximum throughput of 60MB/s (but it's really nearer 55MB/s in 
the real world) (compared with 133MB/s of PATA), per host adapter.

Cheers,
Al.