I'm finishing up my first build and I'm about to connect two PCI-E cables from my Corsair 750W V2 to my GTX 570. However, upon closer inspection of the four available PCI-E cables, I noticed two have black stripes down the yellow wires going into the connector, as well as a fluorescent yellow dot on the connector by where the wires go in. The other two have nothing on the connectors, and the yellow wires are solid yellow...
Are these different voltages or kinds of PCI-E cables, or are they just maybe from different assembly lines?
I can not answer that question apart from that if they are PCIe power connectors they have the same voltages! The only different ones I know are 6pin and 6+2pin connectors, still the same voltage though.
If it's a single rail PSU, the PCIe cables all have to come from the same +12V circuit. I would use the cables in color coded matching pairs. But I doubt it would make any difference which pair of cables you used. It is probably just identifying the cables for you to pair up for 2 x 6 pin connections.