I recently picked up an RX 9070 XT to use with a Ryzen 7 7700X. My previous graphics card only needed two 8-pin power connectors, but the new card appears to require three 8-pin connectors. My 850W Cooler Master power supply currently has all its PCIe cables in use, and I was wondering whether I can buy an additional cable for the third connector. Is it safe to use a replacement or extension cable, and where should I get one?
4 Answers
Using two proper PCIe cables, with one of them being a daisy-chain cable that has two 8-pin connectors, is generally acceptable for a card in this power range. Make sure every cable is an original cable for that PSU or an exact, manufacturer-approved replacement. Don’t mix modular cables from different PSU models.
Don’t use a modular power cable from another PSU, even if the plug looks identical. The wiring on the PSU side can differ, and using the wrong cable could damage the graphics card, PSU, or other components. Only use a cable specifically confirmed to be compatible with your exact Cooler Master model, or replace the PSU with one that includes enough PCIe cables.
That’s fair—I won’t risk using an unverified cable. Thanks for the warning.
Before purchasing a replacement, check both the original PSU packaging and the cable compartment behind the motherboard tray. If the required cable is genuinely missing, contact Cooler Master for an exact compatible replacement rather than buying a generic modular cable.
An 850W Cooler Master unit that supports this kind of graphics card would normally have enough PCIe leads, including a cable with two 8-pin connectors. Check the PSU box and the space behind the motherboard tray in your case before buying anything. The unused cable may simply be tucked away out of sight.
All the visible PCIe cables are currently connected, but I haven’t checked behind the motherboard tray yet. I probably should have looked there before assuming I needed another cable.
So using the available 16-pin worth of connectors plus the daisy-chained connector should be okay, as long as the cables are the correct ones for my PSU?