SATA cables Over 1 meter...(What Happens?)

i imagine that the data would degrade and therefore become unreadable over 1m. unless you get something like a repeater for sata which is unheard of(as far as i kno)

im curious why is your drive that far away? :?

i just had a thought, what kind of motherboard do you have?

i kno my asus board comes with pci plates that allow me to connect external sata drives to my internal sata ports, if you could find one of these you may be able to rig it up, to give you the length you need i also believe these pci plates use a seperate power connecter.



at the top right is the pci thing im on about.

i was thinking more allong the lines of modding the plate so you could use the connectors to join several SATA cables together(to give the length) in a internal config.

WOW, It has been awile, but I beleive it has to do with the power/frequency ratio. I do not think the controller supplies enough power to carry the signal past the magic 1m spec.

Like I said it has been awile since Electronics class.

The internal SATA specification has a transmitter minimum voltage specification and receiver minimum voltage sensitivity specification that allow the expected signal attenuation over 1 m.

At further than 1 m, the signal attenuates enough such that the signal will be below the receiver minimum voltage sensitivity specification. The receiver will likely not be able to correctly decode the signal in all circumstances, resulting in transmission errors.

The eSATA specification has raised the minimum transmit voltage and lowered the minimum receiver sensitivity voltage to allow signal attenuation that would be expected over a 2 m cable. Also, unlike internal SATA cables, the eSATA cables are shielded to prevent EMI/RFI interference, their contacts inside the connecter are more recessed to prevent electrostatic discharge, the connectors are a different size/configuration to prevent using internal SATA cables in the external eSATA specification, and the connectors are rated for 5000 insertions, not 50.

By the way, the PCI plate shown in the picture above that allows an internal SATA cable to become an eSATA port is a recipe for disaster. It is NOT eSATA compliant. Anyone who uses that thing is taking a gigantic risk with the data on that hard drive. It's just like the irresponsible manufacturers who make 24 inch 80-conductor PATA cables (very non-compliant, spec is 18" max) -- you're just dangling your data out the window. Will you have a problem? Maybe "not". Maybe "not yet". 8O

Don't want to unduly split hairs, but the error correction that occurs is due to the data being corrupted.

The question that was posed spoke to cable length issues. Excessive cable length results in signal attenuation and reduced signal to noise ratios, hence data corruption.

Error correction is merely the source of the resulting performance degradation. In and of itself, error correction doesn't negate the fact that data errors are occurring, it confirms it.

That must be why they call it "correction".

Here's what he asked:

Has anyone tried an internal SATA cable over 1 meter long? I need an extra long cable and I can find 1 meter long internal cables but my total length may be near 1.5 meters. I know the specification says 1 meter, but has anyone tried longer cables? What happens?

That's what I answered. Go back and read the replies in sequence. While you're at it, read the "somejoe777" post. He has it right, you don't.

BTW, you know nothing about me or my "type" other than on this issue, I'm right and you're only half right. A bit like being half assed, don't you think?

I realise this has been said here but I wanted to make sure no-one felt the transmission errors would translate into corrupt drive data.

So summarizing you can have a longer than 1m internal SATA cable, but you risk the chance of data corruption (which would be error corrected). The only downside would be a performance hit due to the corrections taking place.

Do others agree with this ?

I am guessing that the cable shown at the link below, which is a shielded 6ft SATA II (eSATA) cable might be a worthwhile choice in this application. As it might reduce the possibilty of transmission issues.

http://www.pcmicrostore.com/PartDe [...] p:10503800

Am I right in assuming that an eSATA cable is fully backwards compatible with a standard SATA cable ?

And how do you know this to be true? For you to offer this as an absolute fact assumes you have tested every cable, drive and M/B controller combination. I seriously doubt that's the case. BTW, not all data errors get corrected.

You just don't get it, do you? Read somejoe777 for the facts.

Both of you guys need to shut up.

You are both right in that data corruption happens and that it does get corrected before it gets written to the HD. Somejoe was right about hanging the data out to dry because there is an exponentially greater risk of uncorrectible data loss at cable lengths out of spec. Sure data correction happens seamlessly with no user intervention. This causes the vast (and I do mean vast) majority of data to be unharmed. But eventually there might be a few bits that get lost here and there that get corrected incrorrectly and cause true data corruption.

Bottom line? There is a spec for a reason. If you need cables that are out of spec, go with a different spec. If you need the E-SATA functionality, get an E-SATA card. If you do use standards that are out of spec, you will most likely start losing the performance gains that you have by using SATA.

Suggestion? for significantly over 3m cable lengths, get an external enclosure that either has ethernet or usb or firewire functionality and has SATA connectors on the inside. USB is rated to about 5 meters I believe (2 meter cables are common, and I've seen them to more than 5), and the performance will likely be better than with an extra long SATA cable. Thats just how the technology works now . It may change in the future.

P.S.
I believe the E-SATA backplate uses an actual E-SATA connector on the motherboard. It is made especially for that purpose.

Attenuation: (N) Reduction of signal strength during transmission. Attenuation is the opposite of amplification, and is normal when a signal is sent from one point to another. If the signal attenuates too much, it becomes unintelligible, which is why most networks require repeaters at regular intervals. Attenuation is measured in decibels.

Everytime you use a longer cable, God kills a kitten.

Basically the way it works is this, if you can find a longer cable you can use it and it will probably work and work well. But...you are risking your data by doing so, and you shouldn't put anyting important that can't be replaced on that drive.

Then use a USB adaptor and you can go 6 feet easy.

Dude, that was like 4 months ago, let it go already.

I meant no offense, but as I recall you two were arguing over nothing of consequence.

And its just a forum...
http://merriam-webster.com/dictionary/vaporized

I think that vapourised sounds so much more beautiful than vaporized.

Um... shouldn't a test be designed to more closely emulate the end user environment? What user sits next to their PC while their hard drive is in China?

Anyways, with a cable that is too long, it is susceptible to more outside electromagnetic interference. In short, EMI will slightly add to the signal on the cable. Enough interference gets added to your signal, and your digital 1s and 0s become difficult to differentiate. Get a repeater to clean up the signal, or get the hard drive closer to the box.