Spec Will Cut External Drive Power Cords

Lucas123 writes "The Serial ATA International Organization just revealed that it is well along the way to finishing a specification that would remove separate power cords to external SATA drives or optical disk drives, allowing them to draw power from the host system. The resulting new cable, being called Power Over eSATA, will be compatible with the existing eSATA connector and support the current maximum interface transfer rate of 3Gb/s. The SATA organization expects the new cables to be released later this year to drive makers."

Comments

Re:USB? Firewire?

[jandrese]

I think the advantage is supposed to be cost and speed. eSATA is faster than USB and Firewire (I think, dunno about the latest Firewire) and requires absolutely _no_ on board logic to work. With this new spec an external eSATA case is literally a metal box with a hole in it, maybe a passthrough connector if they're feeling swanky. They don't even need the transformer anymore. That makes it cheaper than USB and especially firewire.

Re:Cables

[Jackie_Chan_Fan]

They also snap off and break! The piece of shit plastic slot on the hard drives, snaps off with ease.

The durability of Sata connectors suck.

Re:USB? Firewire?

[Solra Bizna]

FireWire is a fairly general-purpose specification, designed so that devices that require a fixed (and quite large) amount of bandwidth can be guaranteed it, and designed with device-to-device communication in mind. Its maximum bandwidth is 400Mbps (unless you count FW800, which I will as soon as I see a device that supports it).

SATA is a storage-device-oriented specification, designed pretty much so that drives can pump data over it as fast as they can read it, with a centralized paradigm and a much higher peak bandwidth at 1.5Gbps (or 3Gbps, but see the note about FW800 above).

Using USB for storage devices is perverted and wrong; it's synchronous, so your practical bandwidth is limited by the length of your cable and the response time of the nodes at either side. On the other hand, a design like that is pretty great for things like user input devices, which is one reason nobody ever talks about making FireWire mice.

So, in summary, SATA is more suitable for disks than FireWire, and USB is dog-slow. Any questions?

-:sigma.SB

Re:USB? Firewire?

[TheRaven64]

unless you count FW800, which I will as soon as I see a device that supports it FireWire 800 has been around for ages. My old PowerBook (4 years old) and my 'new' MacBook Pro (1 year old) both support it and I have had two external LaCie hard drives for three years which have two FireWire 800 ports which allow drives to be chained together.

The spec has allowed 3200Mb/s over fibre for years but I've not seen any consumer products supporting it. The latest version of the spec (just approved) supports 3200Mb/s over the same cables and connectors as existing FireWire 800 systems.

Re:Existing power situation with SATA is hilarious

[Gat0r30y]

7 pins, but just 4 wires going in (unless you got a 3.3V line too which is not necessary on the bulk of SATA drives). The 7 pins make it hot swapable, you can just yank power to a drive, and it doesn't hose the whole thing. I do failure analysis on hard drives all day (its my job), and for me it is about the best part of the SATA spec (since I don't have to reboot machines just to throw a different drive in for testing).
On another note, I'd guess this is also why it took so long to come out with an eSATA power spec that would work, since occasionally it matters whether you pull the SATA cable or the power cable first. Pulling power first is generally the way to go, as sometimes if you pull the SATA cable first the machine will get pissed, and you gotta reboot as your SATA controller will just sit there waiting to hear back from the drive that no longer has a connection.