BIOSTAR B450MHP ВЕРСИЯ 6.2 - Нет POST

Hi,

So I got a faulty BIOSTAR B450MHP VER 6.2 board off eBay. Seller said it stopped working after a successful BIOS update and no further testing had been done. When I got the board, I did my usual resistance measurements on the 24-pin connector/CPU 12V connector and some other coils nearby to verify there's no shorts. After that, I tried booting to see what the board did.

It responds to the power button. The GPU fan starts off at max speed like it usually does and then slows down (which is what happens when the board is about to POST). On my bench supply, I see current draw that's jumping around. It jumps to around 5.3A and then goes back down to around 2.8A. It does this continuously. It's like it's boot looping and trying to start something but can't. There's no display and no USB power (keyboard lights aren't lit up).

1st up, I tried re-flashing the BIOS with my external programmer just to see if it was a BIOS issue. Unfortunately the same issue occurs. So I checked around the board for some voltages. I was seeing 0.9V, 1.8V, 2.5V, 1.2V, 1V (VCORE), 3.3V, 5.1V, 11.8V (seems to occasionally drop to 11.5V). I've also done a visual inspection under a microscope to see if there's any physical damage or knocked off components. I can't see anything damaged or knocked off.

There's no boardview/schematic for this board, so I'm not really sure what to check. Not really sure how the board would stop working after a successful BIOS update so thinking maybe seller did something else to this board and didn't say.

Anyone have any ideas what might be wrong? It seems like it wants to start up as I do see a current spike to 5.3A, but it just drops back down to around 2.8A and tries again and again.

Lol wow

Turns out the issue was someone put the jumper cap in the wrong spot at the JCMOS1 header. I moved it back to its original spot and now the board POSTs. Just to make sure it was that, I put it back in the wrong spot and same fault occurred. Wasted quite a bit of time on such a simple issue.

I did notice what seems to be a missing inductor or something near the SIO

Without a boardview, I am not sure what it exactly is or what it even is supposed to be for. Board seems to work fine without it. Maybe it's not critical. If anyone knows what it might be, do tell as I would like to solder it on. I compared this area against another board pic and the component is there, so it is supposed to be there.

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