I remember reading somewhere on this forum that for 16-->16 cables, you want to look for extenders that use three separate ribbon cables. I don't know if there is anything to this, or why it would be the case, but I noticed that yours only use two ribbon cables. Also, it would help to know what motherboards you are using.
The Cablesaurus 16x/16x extenders have three 'split' sections, but there's really only two 'ribbons' if they weren't split (which they don't need to be). Any extender with only a single ribbon cable is asking for trouble - PCIe connectors have pins on both sides of the connector, so you need two ribbons.
The ribbon cables are also a rather tiny gauge, so using two ribbon cables splits the +12V and +3.3V power among multiple wires. This keeps the extender from overheating and starting a fire / frying your card.
I was talking about the split sections on each side. I agree they don't need to be split. But people do seem to be reporting more problems with the 16-->16 extenders that don't have three split sections per side. Even for the 1-->1, some extenders are split into two sections per side, and these may be better cables. If there is anything to this, and I'm not claiming there is, it probably has to do with manufacturers. Perhaps the manufacturer(s) that use split cables make a better quality product. It's just a superficial mark of the manufacturer, like the locking tab, which also shouldn't matter.
