Simple question about SATA cables

[silentcrs]

Is there a difference between cables rated for 3 gbps and those labelled 6 gbps? Or is it the same cable essentially?

 

[SickBeast]

I've heard of people getting better performance out of a 6gbps cable but YMMV.

If you have a crappy old mangled and messed up cable it could probably make your performance suffer.

 

[Soundmanred]

They are the same cable.

 

[Old Hippie]

They are the same cable.

QFT and the same for SATA 1.5Gb/s.

 

[hanspeter]

No, not all cables are the same.

 

[Soundmanred]

No, not all cables are the same.

link?

 

[corkyg]

Yeah - there are different lengths, some are shielded, some are not. It is the linked device that really determines the data rate, not the cable.

http://www.tomshardware.com/forum/300583-31-sata-sata-cable

 

[hanspeter]

It is also about signal. Signal degeneration is worse in poor cables.

 

[Voo]

It is also about signal. Signal degeneration is worse in poor cables.

And they're still certified for the specific standard. And for the usual sizes inside of PCs you've got to get a really bad cable to get problems.
But sure you can buy longer cables that still reach the specified specs and can be used for special scenarios, but for the average customer? All the same.

 

[Soundmanred]

It is also about signal. Signal degeneration is worse in poor cables.

The question was not about good or poor cables - it was about different cables for 3G and 6G, and there are no such things except manufacturer labelling to get people to buy them instead of using cables they may already have.
It happened wih USB 1.1/2.0 cables as well, and there is no difference there either.

 

[Old Hippie]

No, not all cables are the same.

 

[Emulex]

i have found the 4x sas cables work quite well since its the same cable (infiniband) and well they've had 6G for years ahead of sata (plus sas is full duplex which sends more data). SAS SSD = omgwtf full duplex rules over sata. unless you are doing 1-4QOPS only

 

[sub.mesa]

Note that SAS has a higher signalling strength, and would allow cables up to 10 metres long, instead of the normal 1.0 / 1.5 metres for SATA cabling.

 

[corkyg]

It is confusing to many when acronyms are used without definition. SAS = Serial Attached SCSI. That really is a different thread.

 

[sub.mesa]

Since the thread is about cable length i figured it would be nice to mention the longer size the cables can be when using SAS HBA, for example commonly used when building a ZFS server with Intel SASUC8i SAS controller, connecting normal SATA disks to it.

I have no idea whether the SATA disks can use stronger signalling and thus cable lengths as well, or whether that would require a SAS harddrive as well.

Sorry about not explaining my acronyms, though.

One more relevant thing: to test whether you have cable errors, you can simply query the SMART data on your disk. Look for the property called "UDMA CRC Error Count" and check it's raw data value. This should be zero. If it is not, you had cable errors in the past. If the number keeps rising then you should replace the cable. This affects the data cable only; not the power cable. For the power cable you can check "power-off retract count" in the SMART output.

A common Windows-application that can read SMART data is HDTune (check the Health tab).

 

[Emulex]

i'm pretty sure the sata data portion is identical. the sas drives use ULVD (low voltage differential) signalling where as the sata is lower voltage simpler signalling. which is why old cages couldn't mix but now you can mix sata and sas.

Kinda like ECC memory. SAS. Reliability.

non-ecc.sata.crash0rz