Question Red Light On Silver Stone SST-ST1200 PSU, should I replace it?

[MutualBenefits]

I brought a used Silver Stone SST-ST1200 PSU for my computer build that I’ll list below , when plugging the PSU to the wall (not connected to other hardware) the LED light is red on psu. When I connect the PSU to the motherboard it either doesn’t power on or fans turn on for a quick second then cut off with the led being red on psu… What would be the best power supply wattage for my build below since I’ll likely have to purchase a new one.

Ryzen 9 5900x on Asus Tuf gaming x570 - pro Wi-Fi II
64GB DDR4 Ram @ 16GB * 4 via 3200 mhz
Samsung Evo 512GB SSD
Cruical 1TB SSD
4TB SeaGate Hard Drive
Asus Strix 3070 or RTX 2080
Replacing a Silver Stone SST-ST1200 PSU

 

[Lutfij]

You should look into a 750W reliably built, branded PSU. If you still have the sellers contact info or a method to get a refund, return the PSU and get your refund. You shouldn't be investing in an used PSU unless you know the seller first hand and you know what the PSU was used for. Very likely that the PSU was used for mining which would reduce it's lifespan drastically to the point of it being an expensive paperweight.

Could you inspect the motherboard for a sticker that has a 4 digit number signifying the BIOS version that the board came shipped with? If you have BIOS version 0305 or above, you're fine with the processor on that board.

 

[MutualBenefits]

4403 or KF42, so red led on the psu means it’s dead even if it isn’t connected to anything right. He said he tested it using a tester saying it’s working before selling it to me, though once I’ve connected it to the wall after building my pc over with a new mobo, other than a led light on mobo nothing else comes on

 

[Lutfij]

4403
That's the latest BIOS then for the motherboard.

I'm trying to find the LED you speak of since images of the PSU off of Google don't show it. In either case, I wouldn't rely anything on a used product, not when the mining craze is yet around and people are trying to make quick work of unsuspecting customers.