6-pin to 8-pin adapter VS. 2 molex to 8-pin adapter

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ldewitt

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Sep 27, 2013
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What should i use I have a Gigabyte GTX 770 4GB that uses 2 8-pin connectors but i only have one 8 pin and one 6 pin. Should i use the 2 molex to 8-pin adapter or should i buy a 6-pin to 8-pin adapter?

Thanks for your help.
 
Solution
The 8-pin PCIe connector has 2 additional ground (neutral) pins vs the 6-pin. It does NOT have additional +12V wires. The additional grounds lower the total CONNECTOR resistance and allow more power transfer, but in reality a 8-pin does not have twice the capacity of a 6-pin (which the 150 watt vs. 75 watt rating would imply).

Two molex to one 8-pin is a better solution than 6-pin to 8-pin, since each molex can handle 2 ground circuits. The molex connector is rated for 8 amps per pin on standard 18 ga. wire, so 2 connectors (2x +12V and 4x ground, total) can handle more than 192 watts on the +12V and 384 watts on the ground circuits.

If the card has 2x 8-pin connectors, you MUST connect 2x 8-pin power sources. The PCIe slot and a...
i've seen 2 choices on the web. first one is 2xmolex to 2x(6+2 pin) and the other is 2x molex to 1x 8Pin PCI-E.
should i get the single 8 pin or the other? the 8 pin seems to me the better choice...