Question Putting my RAM in slots A2 and B2 doesn't boot my PC at all

[xAlfafllfflx]

I have a situation with my current RAM slots on my MSI Aorus B450M VDH-MAX AMD. It happened last week where my PC suddenly froze and powered off. I figured it wasn't too drastic and tried powering on the PC again. But once I pressed on the Power, the PC doesn't boot up at all. Checking the Mobo's "EZ Debug LEDs" lit up the "DRAM" LED and stopped from there. (It usually cycles from "CPU" LED up to the 4th labeled LED). I figured it was a RAM problem and placed my RAM in slots A1 and B1 and it works just fine. I was hoping to know what's my situation here and is there anything I can do to fix it?

Additional Information:
-I bought myself those compressed air cans with the nozzle to see if the RAM slots were just dusty but I didn't want to go through with it yet if that isn't the problem in the first place.
-I checked the RAMs itself using MemTest and it passed all 4 Passes without any hitch.
-the RAM sticks itself are two HyperX 8GB 2666MHz DDR4

 

[Colif]

MSI Aorus B450M VDH-MAX AMD

MSI don't make Aorus Motherboards... no wonder Google search showed 2 results.

assumed Motherboard manual - https://download.msi.com/archive/mnu_exe/mb/M7A38v8.1.pdf

1 stick - A2
2 sticks - A2/B2
4 sticks - obvious

So it only recommends A2/B2, it doesn't say you have to

Try putting both in the 2 slots that are having problems and run memtest again. It is always possible the cause is the slots.

 

[xAlfafllfflx]

MSI don't make Aorus Motherboards...

I apologize I was making this post outside and forgot the brand itself. I've recently rechecked and its just MSI B450M PRO-VDH MAX

Try putting both in the 2 slots that are having problems and run memtest again. It is always possible the cause is the slots.

I've tried putting the RAM sticks on both slots but it doesn't even go to BIOS. It's a straight up black screen while the Motherboard has the EZ Debug LEDs have "DRAM" and "CPU" lit up.

 

[Colif]

It seems unusual for the slots to just stop like that.

What are rest of specs? makes me wonder about power as I don't know why slots would randomly stop working

 

[xAlfafllfflx]

It seems unusual for the slots to just stop like that.

What are rest of specs? makes me wonder about power as I don't know why slots would randomly stop working

GPU MSi GTX 1050Ti 4GB
CPU: Ryzen 5 3600
CPU Cooler: AMD Wraith Stealth
RAM: 2x8GB HyperX 2666MHz
PSU: Corsair CV550
Storage: -1TB SSD
-256GB SSD
-1TB HDD
Coolers: 3x120mm Air Coolers (2 Front, 1 Back)

 

[Colif]

I am not sure if PSU might have damaged slots. Its about only thing I can think of doing it while the PC was actually running. Could have been a power surge.

checking to see what might be cause