With horrible pc parts price I bought this Office PC with a Asus Prime B360M-K to upgrade as a gaming pc but the chiniese GTX 1650 Low profile I bought does not boot sometimes. It gives 1 long beep and 3 short beeps gap and another beep. card fan does spin all the time.
Look closely at OP’s original pic. I’m pretty sure the power for the card is coming through an old 20 pin connector from that dodgy power supply, it doesn’t even have a 24 pin connector.
Looks like a 24 pin to me, but it’s blurry and who can say.
Either way an old oem psu isn’t the way to go.