Question Dual Channel RAM Suddenly Stopped Working

[akstudio]

I was just browsing and suddenly displayed went out, but the keyboard and fans still on. I restarted my PC and still no display and the first thing I assume is the RAM (I have 2 slots only). So, I did some reseats multiple times until I decided to leave 1 RAM stick only on the first slot and display finally showed up. Every time I insert the other RAM back it always shows no display when booting. I encountered this problem weeks after I installed a new CPU (from APU), PSU and GPU

is my mobo slot faulty or the RAM itself

EDIT

UPDATE : PROBLEM FIXED

I reseated this (https://ibb.co/xDgXCMV) cable and my dual channel RAM got finally recognized. absolutely did not expect that

 

[faalin]

Please add full system specs with make and model.

Is windows full up to date?
what cpu did you go from and what cpu do you have now? Is the bios up to date?
Try removing and reinstalling the cpu, clean and re apply with new thermal paste.

Put one stick in and run memtest https://www.memtest86.com/ Let it complete and then stick the other stick in and run again, no errors allowed.

 

[akstudio]

gtx 1660ti
Ryzen 5 3600
coolermaster hyper 212 black edition
Corsair sf600w platinum rated psu
memory (Kingston HyperX DDR4 RAM 2X8 gb)


old specs
ryzen 3 3200g
some aftermarket cooler
cv450 450 watts bronze rated [psu
(same ram)


windows 10 is up to date. same with BIOS

When I insert the other stick on the same slot my current stick is in right now, display does not show
. note that I have to perform a lot of reseat for the display to show

 

[akstudio]

gtx 1660ti
Ryzen 5 3600
coolermaster hyper 212 black edition
Corsair sf600w platinum rated psu
memory (Kingston HyperX DDR4 RAM 2X8 gb)


old specs
ryzen 3 3200g
some aftermarket cooler
cv450 450 watts bronze rated [psu
(same ram)


windows 10 is up to date. same with BIOS

When I insert the other stick on the same slot my current stick is in right now, display does not show
. note that I have to perform a lot of reseat for the display to show

I have also read that over tightened screws from the CPU cooler might also cause the motherboard to hardly read the DIMM slots or something like that, but I believe it's unlikely since the system ran properly

 

[akstudio]

UPDATE : PROBLEM FIXED

I reseated this (https://ibb.co/xDgXCMV) cable and my dual channel RAM got finally recognized. absolutely did not expect that