On Fri, Dec 06, 2019 at 09:50:45AM -0500, D. Hugh Redelmeier via talk wrote:
Why does it make sense to omit a ground line? If it is specified to be ground, it ought to be supplied as ground. As I read it, the power supply must supply ground on all the ground pins but the video card is free to not use some of them.
If one of the pins from the power supply isn't connected, then the cable is defective.
As long as all 8 pins in the GPU side are connected, it is fine. There doesn't need to be 8 wires going to the power supply to do that.
Note: it might be connected within the connector itself via an internal jumper.
Since the 2 sense wires are just to allow detecting the cable type, they don't carry much current at all, and nothing wrong with connecting them together with a single wire from the power supply side. They are connected to ground, but not used as ground for the power carrying part of the cable. -- Len Sorensen