Posted on January 21, 2010 by by robtheailean

Forgive my testiness, but I am getting really irritated by the mainstream journo’s (and the Twitter Twits…).

There was an article written by David Frith in Tuesday’s Australian (19th Jan – IT section) about how with USB 3 you would get 2.5GB/sec data transfer doing backups to an external drive. As usual, “DoubleClick” as he calls himself, has regurgitated some press release or other (as do most so called “professional” journalists in IT) and left everyone looking forward to lightspeed backup performance.

Lets look at this scenario in some objective detail:
The fastest (in most areas) hard drives are the 15,000rpm SAS hard drives (as found in servers).
The MAXIMUM SUSTAINED not BURST transfer speeds of these units are 204MB/sec – did I mention this drives costs around $1200 and has a capacity of 600GB’s?

Now for a reality check; for the average PC owner, the most expensive  SATA III/6GB/s  hard drive from Seagate, the 2TB, ST32000641AS (average cost, $450.00) has a SUSTAINED data transfer rate of 138MB/sec ACROSS THE SATA INTERFACE. (So this is the speed that the hard drive can deliver data to the bit where the SATA cable plugs in…)

 You now have to get the data across PCIe bus (as in the connection on the motherboad that connects the slots on the motherboard where addon cards get installed) to the USB controller and then to the backup (external disk) via the USB to SATA conversion circuits (read: more delay).

So the Reality is the 3GB/s speed claim is the SPEED oF  The  INTERFACE; great for Press/Media Releases and lazy, plagiarist journo’s – but no true picture of the actual speed the end user will see…

So, no David (et al), you are NOT going to see 2.5GB/s backups, but with a USB 3.0 external HDD enclosure AND USB 3.0 ports in your PC AND good hard drives at both ends you MAY see them backup, at best, 3 times faster than your existing USB 2.0 setup.

Assuming nothing else is happening on your PC…. this means 25-30MB/sec, at best; so about 1 percent of the claimed speeds – and they say the Advertising Industry is fine being self regulated.

USB 3.0/SATA 3.0 - Hype or reality???, 5.0 out of 5 based on 1 rating

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