Storage Solutions External Hard Drive...

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ibmmainframes said:
6 times faster than USB.
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I have eSATA and USB2 Vantec cases and I get 35mb/s with USB2 and same HDD in eSATA case I get 62mb/s. Besides the speed advantage you can load an OS on a HDD in an eSATA case and boot from that HDD.
 
And make sure, your motherboard support SATA hot-swapping. Or it may make trouble with the SATA to eSATA converter.

By performance, eSATA>SATA>FIREWIRE 800>FIREWIRE 400>USB 2.0
 
eSATA and USB2 Vantec cases and I get 35mb/s with USB2 and same HDD in eSATA case I get 62mb/s
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No, 6 times is a theoretical report. SATA is 3Gb/sec while USB 2.0 is 480Mb/sec.

And I am sure, you are not using the approved eSATA spec. eSATA is not the same as SATA. The eSATA spec provides for upgrades to protect data integrity over the longer cabling that is usually employed in an external arrangement. This data safeguarding is accomplished via higher transmit voltages and receiver sensitivities in the host/client and may also include the use of buffer chips. NONE of these things are likely to be present in a standard SATA configuration and they aren't added by hanging a cheap eSATA "adaptor" in your backplane array.

Also be aware that some external HD enclosures that claim to be eSATA compliant are not, i.e., they have nothing more than a eSATA connector tacked on to the IO board. Look for the eSATA logo on whatever you buy. It is not *supposed* to be used unless the device meets the eSATA spec.

Check this to know more about eSATA:

http://www.sata-io.org/docs/External SATA WP 11-09.pdf
 
ibmmainframes said:
No, 6 times is a theoretical report. SATA is 3Gb/sec while USB 2.0 is 480Mb/sec.
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All the therotical knowledge I have on computing would fit on a pin head... all I mentioned was the real life speeds I get with same HDD connected as USB2 and eSATA. Is that not what matters finally ?

Hmmm ... I see you are with Prasad Labs... I ran a Film Process Lab for many years till Digital Cameras killed my trade in the late 90's :(
 
esata>Sata, they're both same arent they;
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Yes, theoretically they run at he same speed. (2400 Mb/s). But eSATA drives performed well in our tests. (The reason is higher transmit voltages, Chipset Buffer & less heat).

Key benefits of eSATA:

* Up to 6 times faster than existing external storage solutions: USB 2.0, & 1394
* Robust and user friendly external connection
* High performance, cost effective expansion storage
* Full SATA speed for external disks (115 MB/s have been measured with external RAID enclosures)
* Identical logical signaling (link/transport-layer and above), allowing native SATA traffic from end-to-end, all disk features are available to the host
* Maximum cable length less than 2 metres (USB and Firewire allow longer distances)
* Minimum and maximum transmit voltage increased to 500 mV - 600 mV (from 400 mV - 600 mV)
* Minimum and maximum receive voltage decreased to 240 mV - 600 mV (from 325 mV - 600 mV)
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But you can't compare a eSATA to USB2.0. Even a FIREWIRE 1394a drive beats USB 2.0 (theoretically firewire is 400Mb/s but USB 2.0 is 480 Mb/s).

all I mentioned was the real life speeds I get with same HDD connected as USB2 and eSATA
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No, there were a number of products designed for external connections of SATA drives. Some of these use the internal SATA connector (easily recognized by the L shaped contact ledge) or even connectors designed for other interface specifications, such as 1394. These products are not eSATA compliant. Have you seen a eSATA logo in your adapter?
 
I need to buy an good sleek sturdy external harddisk with case of around 400 to 500gb..which should i buy and what will be approx cost??? pls help
 
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