SFF-8087 cable and connector variations causing fault?

Question

I recently bought a set of 6 cables to connect my LSI MegaRAID card to my Norco-4224 backplane. The connector on both ends is SFF-8087.

However, when they arrived, the disks would not be detected. I thought the cable was faulty, but I tried all 6 and none work. So I borrowed an SFF-8087 cable from my Highpoint Tech RAID card and the disk was detected.

I tried poking a multimeter in, but they seemed to be wired correctly. Although the connectors are very fiddly so I can't guarantee my results.

The connectors between them appear to be different slightly. The Highpoint Tech cables have thick copper on the connectors PCB with varying lengths, whereas the ones purchased with the LSI have thin copper with a horizontal groove.

The ones I purchased look like this: enter image description here

Whereas the Highpoint Tech ones look like this: enter image description here

This has left me very puzzled! And with lots of questions like:

Is this enough to cause a connection fault?
Are the cables themselves faulty or just the connectors?
Do certain cards/backplanes need certain connector types?
Are the different copper lengths to ensure they can be hotplugged?
How does one better describe these differences?
How does one go about testing these cables?

Can you provide the specific model/SKU of the cables you purchased? — ewwhite, Oct 20 '14 at 00:15
You ordered them. You don't have a manufacturer or item number? — ewwhite, Oct 20 '14 at 00:18
I notice that Rosewill RASA-13005 0.5M SFF-8087 to SFF-8087 Internal Multi-lane SAS Cable are the same type as listed on Newegg. — tudor -Reinstate Monica-, Oct 20 '14 at 00:20

score 2 · Accepted Answer · edited Apr 13 '17 at 12:14

I try to stick with the RAID controller or enclosure/backplane manufacturer's cables. Usually that's HP or LSI (sometimes Tripp-Lite) for me, so I haven't seen situations where this did not work. Maybe the odd case of active/passive SAS cabling, but that's extremely uncommon. There's no voodoo involved with buying these SAS cables.

To answer your other questions, SFF-8087 is a standard. I wouldn't recommend hot-plugging internal SAS cables. They seem to have a limited number of plug/unplug cycles.

I'd chalk it up to bad cables or an incorrect spec. As for differences, I'd describe it as "cheap cable" versus "not cheap" :) I don't I've ever proactively tested these before.

SFF-8087 cable and connector variations causing fault?

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