I'm upgrading from an RTX 2080 and am still getting familiar with the newer 12V-2x6 GPU power connectors. My Gigabyte RTX 5070 Ti includes an adapter with three female PCIe 6+2-pin connectors. My Corsair 850W power supply has two PCIe cables, each with a pigtail, giving me four available 6+2-pin connectors. Would it be safe to connect the adapter as shown in the diagram, or do I need three separate PCIe cables? I've seen conflicting advice about whether using a pigtail for this setup is safe.
2 Answers
The safest conventional recommendation is to use three separate PCIe cables for the three plugs on the adapter. If your power supply has a free PCIe socket, you can purchase another cable made specifically for that exact Corsair PSU. If it doesn’t, replacing the PSU would be the alternative, though that may be unnecessary for a 5070 Ti.
Your setup should generally work with two genuine Corsair PCIe cables and one pigtail, especially for a 5070 Ti. The warning about using separate cables is mostly a conservative recommendation based on the nominal 150 W rating per 8-pin connector. Make sure every connector is fully seated and the cable isn’t sharply bent near the GPU. An even cleaner option is buying Corsair’s PSU-specific 12V-2x6 cable, but don’t use a modular cable from another brand or PSU model.
The pigtail isn’t automatically unsafe here. Some Corsair power supplies and their official 12V-2x6 cables are designed to deliver high GPU power through two 8-pin connections on the PSU side, so the actual cable and PSU design matter more than simply counting connectors.