I have an MSI B550M PRO-VDH WIFI motherboard, and it looks like one of the first three RAM slots has stopped working. When I booted my PC with RAM in one of those slots, there was no display, and the DRAM light stayed on solid. Right now, only the last RAM slot is functional. I've also tried reseating the CMOS battery, but there's a lock on it that I can't remove, and I don't have tweezers handy to help with that.
2 Answers
It honestly sounds like it could be a faulty motherboard at this point. If none of those slots are working, there's not much you can do besides testing with a different motherboard or contacting support.
Which specific RAM slot is working for you? You don’t necessarily need to remove the CMOS battery. You can actually short the pins to reset it! Just make sure your power supply is turned off and unplugged, then use a screwdriver to briefly connect the two pins that hold it in place. That's a quick way to reset it without removing the battery.

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