Why there are only 6 wires for the RTX cable?
It is by Nvidia's design for the RTX 3050 3060 3070 to use 6-pin only.
For 3050/3060/3070, the GPU is only using 6-pin of the 12-pin header, and this is why it requires only a single 8-pin PCIE connector.
For 3080/3090, the GPU is using all 12-pin of the 12pin header, and it requires dual 8-pin PCIE connector (6-wires from each 8-pin port, 6+6=12)
You can check the original 12-pin adapter of 3050/3060/3070, it is also using 6-pin only.
There’s also the new-fangled Founders Edition power connector, with up to 12 pins, but like the GeForce RTX 3070 only 6 of the 12 are populated for the RTX 3060 Ti, so there’s only a single cable which converts 8-pin PCIe to the new Nvidia connector, compared to the RTX 3080 which uses a Y splitter for two 8-pin PCIe connectors. This is more than enough to feed the 200W TDP that the GeForce RTX 3060 Ti boasts, and it usually hovers in the 180 to 200W mark at stock, depending on whether you’re using RT and Tensor Cores. (http://www.redgamingtech.com/nvidia-killed-the-rtx-3070-rtx-3060-ti-review-benchmark/)
On the RTX 3070, NVIDIA doesn't need that much power, so the adapter cable uses only a single 8-pin. Total available power is 225 W (150 W from the 12-pin + 75 W from the PCIe slot). With every Founders Edition, NVIDIA includes a 8-pin to 12-pin adapter cable, so you're good to go and don't need any special adapters. On the closeup of the 12-pin adapter, you can see how only half its pins are populated. This ensures that on a RTX 3080/3090, this adapter will not work, as those cards require power on all pins. (https://www.techpowerup.com/review/nvidia-geforce-rtx-3070-founders-edition/4.html)
For 3050/3060/3070, the GPU is only using 6-pin of the 12-pin header, and this is why it requires only a single 8-pin PCIE connector.
For 3080/3090, the GPU is using all 12-pin of the 12pin header, and it requires dual 8-pin PCIE connector (6-wires from each 8-pin port, 6+6=12)
You can check the original 12-pin adapter of 3050/3060/3070, it is also using 6-pin only.
There’s also the new-fangled Founders Edition power connector, with up to 12 pins, but like the GeForce RTX 3070 only 6 of the 12 are populated for the RTX 3060 Ti, so there’s only a single cable which converts 8-pin PCIe to the new Nvidia connector, compared to the RTX 3080 which uses a Y splitter for two 8-pin PCIe connectors. This is more than enough to feed the 200W TDP that the GeForce RTX 3060 Ti boasts, and it usually hovers in the 180 to 200W mark at stock, depending on whether you’re using RT and Tensor Cores. (http://www.redgamingtech.com/nvidia-killed-the-rtx-3070-rtx-3060-ti-review-benchmark/)
On the RTX 3070, NVIDIA doesn't need that much power, so the adapter cable uses only a single 8-pin. Total available power is 225 W (150 W from the 12-pin + 75 W from the PCIe slot). With every Founders Edition, NVIDIA includes a 8-pin to 12-pin adapter cable, so you're good to go and don't need any special adapters. On the closeup of the 12-pin adapter, you can see how only half its pins are populated. This ensures that on a RTX 3080/3090, this adapter will not work, as those cards require power on all pins. (https://www.techpowerup.com/review/nvidia-geforce-rtx-3070-founders-edition/4.html)
Updated on: 14/06/2022
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