Question System no longer displays video or shows black screen

[FoxTypeSystemReq]

I have had this PC build for just over two years now, and the current graphics card for about half a year. The PC was working fine just last night but tonight has stopped working. With no prior indication of any issues, my build no longer outputs video or just outputs a black screen (the monitor indicates a video signal is received but nothing shows). During one occasion, it output a black screen with a single non-blinking DOS-style cursor in the upper left corner, but the rest of the symptoms remained the same. On the motherboard are four status LEDs, from bottom up they are BOOT, VGA, DRAM, and CPU. The VGA one stays solid white once it is reached (I do not know if these LEDs can be any other color). I have tested the monitor and cables and other connections, all fine with anything else I've plugged in. I have tried plugging in another monitor and cable, no change. I have tried moving the graphics card from one PCI-E slot to another, no change. I have tried swapping in another graphics card which was previously in the PC, no change. I have tried re-seating the RAM, no change. I have moved around a number of power and other cables, still no change. It seems the graphics cards receive power as normal and don't indicate any error on them that I can tell. Everything is slotted or plugged in securely during each troubleshooting phase.

I am beginning to suspect that there is an issue with the motherboard, but the issue may be elsewhere, and I am wondering what else I can try or what else it could be and how I could confirm this. I've tried asking someone else outside of here who referenced a previous topic here of a similar issue but different status LED that ended up being a faulty outlet, and I tried a different outlet as well to be sure, but I haven't gotten anywhere with this. I've just made an account here to try to get help with this issue since it's the first option that came to mind right now, and I appreciate any help I can get.

My full specs are listed here on PCPartPicker which I used to assist in compatibility. In short, motherboard is MSI B450-A PRO MAX ATX AM4, CPU is AMD Ryzen 7 2700X 3.7 GHz 8-Core, GPU is EVGA XC GAMING GeForce RTX 3060 12 GB, backup GPU I tried swapping in is Zotac AMP GeForce GTX 1080 Ti 11 GB, and running Windows 10 with the latest stable update released November 2022.

 

[Lutfij]

Welcome to the forums, newcomer!

Try and borrow a reliably built PSU with at least 650W of power at the entire system's disposal to rule out your PSU being the root cause of the issue(not getting enough power). You can likewise take the discrete GPU over to a donor system to see if the card works as it should without a hitch to narrow down your GPU not being faulty. You can then try and work with the BIOS flash option on your board(Page 40) and see if that revives your board.

 

[FoxTypeSystemReq]

I don't have access to a spare PSU or system right now so I opted to reset and update the motherboard BIOS. That seems to have fixed something, now it's booting normally like it used to and I currently don't see any issues running tests, just going to see if it holds.