Xbox series s powers on, fan spins then stops no signs of life

Hello

I got an xbox series s off of ebay a while back, the listing said that it had an hdmi issue.

After doing brief trouble shooting I decided to replace the retimer chip, as the port its self was in good shape. The replacement went fine as I’d done it a few times before on other consoles.

However, I then realized that the issue wasn’t the hdmi or retimer. When I power the console on it beeps, the light turns on, and then the fan spins for roughly 10-15 seconds. Then the fan stops spinning but the power light stays on. I didn’t want it to overheat so I forcibly turned it off.

Any idea what the issue could be? I’m a little new at this so I don’t really know how to check for shorts or proper voltage readings on the motherboard and I’d really appreciate any help.

Thanks.