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The AMD Radeon HD 6970 uses both an 8-pin and a 6-pin PCIe power connector located at the end of the video card on the top corner. AMD didn't tell us what the power supply requirements are, so we pinged XFX and they were happy to let us know. AMD recommends a 550 Watt or greater power supply with one 75W 6-pin PCIe connector and one 150W 8-pin PCIe connector on the Radeon HD 6970. The AMD Radeon HD 6950 requires a 500W or greater power supply with two 75W 6-pin PCIe connectors.
Você precisa conectar a energia em ambos os soquetes .