I have an HP Z440 workstation with its original 700W power supply. My new Radeon RX 7600 XT needs one 6-pin and one 8-pin power connector, but the workstation's power supply only provides two 6-pin outputs. Should I use a 6-pin-to-8-pin adapter, find an official HP cable, or replace the power supply? The genuine HP cable appears to cost around $30, which is close to what I could pay for a used power supply. I'm also concerned that HP may use proprietary motherboard power connections.
2 Answers
Since the workstation already has a 700W supply, the total wattage may be sufficient; the main issue is getting the correct GPU connectors safely. An official cable designed for that HP power supply is preferable to a generic adapter, but confirm that it is specifically compatible with the Z440 and has the correct pinout. Don’t assume every cable advertised as 6-pin-to-8-pin is wired safely for this system.
Be careful with a simple 6-pin-to-8-pin adapter. A standard 6-pin PCIe connector is generally rated for less power than an 8-pin, so adapting it without confirming the wiring and power limits could overload the cable or connector. Also, an HP Z440 may use proprietary power connections, meaning a normal replacement PSU might not plug directly into the motherboard. Verify the exact HP cable and pinout before buying anything.
I made a mistake in my original wording—the card has one 6-pin and one 8-pin input, not four connectors. I found an official-looking HP cable, but I’m wondering whether replacing the motherboard and power supply is the only reliable alternative.