[clug] another rainy day time filler - CF reader

Alex Satrapa grail at goldweb.com.au
Sun Feb 14 17:26:55 MST 2010

On 15/02/2010, at 10:07 , Paul Warren wrote:

> I'm fairly sure that USB 2.0 has a maximum possible transfer rate of 480
> megabits/s, which is 60 megabytes/s.  But that is only the trasfer rate
> for the USB transport.  USB protocol overheads take a significant whack
> out of that, and there are fairly large delays between packets also.
> - From my experience, the most you're going to get out of a USB connection
> is 25 megabytes/s of actual data transferred.

I have a WD "My Passport" drive which handles FireWire 800/400 & USB 2.0.  I get about double the transfer speed out of FireWire 800 (~50MB/s) as I do from USB 2.0 (~25MB/s), and not quite 50% more out of FireWire 400 vs USB 2.0.  USB is cheap for a reason.

Having said that, I'm getting damned good performance out of my SanDisk Ultra II 8GB CF (it's a black label with red highlights) and my SanDisk ImageMate 12 in 1 "Certified Hi-Speed USB™" reader (model number SDDR-89 V4).  The card's rated at 15MB/s, I average at around 9MB/s.


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