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.
You don’t have enough power supply.
It really seems like replacing that with a higher rated name brand psu will resolve your problem. You’re running up against the maximum power the pcie slot is rated to deliver. Claimed wattage only tells part of the story. All that power for the card has to come through the 24 pin connector along with everything else.
If you wanna prove me wrong plug the motherboard/cpu/gpu into someone else’s higher rated power supply and show that it has the same behavior.
If there’s a computer shop near you they’ll probably do this test in front of you with one of their power supplies for a couple of bucks. If there’s a gamer friend they’ll do it for free to help you figure out the problem.
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.