About three months ago I purchased used ROG Strix Z490-I Gaming motherboard. I paired it with i3-10105f CPU, 32 GB of 3200 MHz DDR4 RAM (with RGB) and two PNY NMVe SSDs. It was direct upgrade from P8H61-I board, also from Asus. The whole build was working perfectly for about three months and went completely dead.
I've powered off my PC as usual and then turned off power strip for the night. I've had USB speakers plugged into the motherboard and they always make a singular "pop" sound, when PC loses its power. This time there was a second "pop" sound but I ignored that and went to bed.
Next day, I powered on the power strip and there was no reaction whatsoever for the power button. Also, built in RGB wasn't working (which it should even before powering on the PC). I've tried resetting CMOS by shorting appropriate pins and even disconnected the battery itself. No change. I've then removed the CPU, SSDs and RAM to confirm that they aren't faulty. I've tried another PSU - no effect. My main PSU is working, because I'm using it right now in my spare rig. The RAM also works in the other PC.
I've tried BIOS flashback function and it does work. The LED starts to flash and after couple minutes turns off. That however haven't brought back my motherboard to life. I've made some measurements too. There is 3,3 V on power button pins and CMOS pins and 5 V standy present on 24-pin ATX plug.
My guess is that there is short somewhere on the board or something isn't creating neccessary voltage. What do you think? Is there something else I could try?