I recently bought an RTX 3070 and currently have a SeaSonic FOCUS Plus Gold 550W power supply. My previous GTX 1650 Super used a single 6+2-pin PCIe cable, but the RTX 3070 appears to require a 12-pin connection. Can I reuse the existing cable, or should I buy additional cables? If two cables are needed, should both be new, or can I combine one new cable with the cable from my 1650 Super?
1 Answer
First check whether your particular RTX 3070 came with a 12-pin adapter. Many cards use an adapter that converts the GPU’s 12-pin socket to two standard 8-pin PCIe plugs. If so, connect the adapter to two PCIe power connectors from the PSU, preferably using two separate cables rather than one daisy-chained cable. Do not buy a random modular PSU cable, because modular cables are not universally wired the same way. Only use a cable specifically made for your exact SeaSonic PSU model, or the adapter included with the graphics card. Your 550W unit may work if it is in good condition and the rest of the system is reasonable, but a higher-wattage PSU could provide more headroom.
The existing 6+2-pin cable is still a standard 8-pin PCIe connector and may be usable through the included adapter, but check the graphics card manual first. Never force a connector or mix cables from another PSU brand.