Question Corsair CX750M - 24 Pin Connector

[ckoaks33]

We're rebuilding our computer and tested the power supply (Corsair CX750M). Pin #14 (-12V) isn't reading anything when we do the paper clip test and look for readings on a multimeter. The rest of the pins read as they're supposed to but Pin #14 does not. Does anyone have any ideas if we need a new PSU or if this is typical?

When powering on the computer, with only the mobo and CPU fan connected, the PSU only powers on for approx 30 seconds, then shuts off for 1-2 seconds, and starts re-cycling. No POST. Nada.

MOBO: ASRock Z98X Killer
CPU: Intel Core i5-4690K
RAM: 4 GB (for now)
GPU: Sapphire Radeon NITRO+ RX 590 8GB

Thank you!

 

[Calvin7]

PC devices on a motherboard that require -12V

1. RS232, RS485 ports without build-in circuitry for generating the negative voltage
2. mini PCI slots.

This is old obsolete technology. Today, -12v isn't used. Power supply manufacturers keep adding the -12V line to the plug as long as the ATX standard requires it. Since it isn't used anymore, all you'll get is a dead wire.

 

[ckoaks33]

So, that being said, any suggestions for a motherboard? (The only reason I have this is it was given to me.)
I'm not a gamer so I don't need a $300-$400 board. Used with a warranty doesn't bother me either.