[SOLVED] Dumb Question about 6+2 Pin PCIe Connector

[ManOfArc]

Looking at my PSU's 6+2 pin PCIe connector I see 6 (+) wires/pins and 6 (-) wires/pins for use as a 75W 6-pin connector. I also see 2 more (-) wires/pins that somehow allow it to become a 150W 8-pin connector. How does adding two more ground wires alone increase its capacity to 150W ?

 

[Eximo]

Fun fact, it doesn't.

The extra two pins are simply there to let the system know that an 8-pin cable is connected and add an extra ground. The 6-pin part carries 3 12V wires and 2 grounds and a sensor.

6-pin cables only have 2 12V wires, 2 grounds and a sensor. 5 wires. The 6th is optional for 75W, and mandatory for 150W.

(Really though more like 60W per wire, there is a lot of wiggle room depending on the wire gauge as well)

 

[ManOfArc]

Excellent answer. Thank you. In that case, what would be the minimum wire gauge size PCIe connectors should have?

 

[Eximo]

24 awg is common on low end units if I recall correctly. 22 and 20 is what you find on higher end units, particularly ones that bundle multiple PCIe connectors on a single cable. And power supplies that offer longer than average length will step up a gauge to reduce voltage drop.

No standard, it varies by the design and expected loads.