Question ASRock Fatal1ty B450 Gaming K4 - - - No POST after CPU upgrade ?

[simpledude]

Hello everyone, I hope someone can help me today.

I've been trying to upgrade my CPU from a Ryzen 5 2600X to a Ryzen 5 5600 (Non-X).

I already had the BIOS flashed to version 5.60 and when I installed the new CPU it just entered a Post-Loop and won't post at all, I've tried using only 1 ram stick, every possible combination of slots, unplugged any peripherals, ssds, even the GPU to no avail, it always does the same thing, it turns on then nothing shows up on screen and it eventually restarts and does everything again, I've removed the CMOS battery, loading default settings with the old CPU before swapping to the new one, I flashed the BIOS to 5.60 again to see if that did anything but nothing works and I've ran out of ideas.

Update: I noticed that after putting back the old CPU that the RAM is stuck at 2133mhz (Used to work fine even with the 5.60 BIOS Version) and that Windows now shows 8GB as "Hardware Reserved".

Here's my setup in case it helps:

CPU: Ryzen 5 5600
GPU: RX 6700 XT
PSU: DeepCool PX-850-G (850w)
RAM: Corsair Vengeance LPX (2x8) DDR4 3000mhz
MOBO: Asrock Fatal1ty B450 Gaming K4
SSD: Samsung SSD 980 1TB
HDD: 2TB

 

[pctech2005]

Have you tried installing a clean version of Windows?

 

[simpledude]

Have you tried installing a clean version of Windows?

Hello, the issue doesn't seem to be windows, since I ran a memtest86 test and noticed that the total memory only showed 8GB, although in the SPD both show up and on the BIOS both show up, an update to this is that

+ I found out that the system won't POST with a single memory stick doesn't work neither on B1 nor B2, it does POST with a single stick for A1 and A2

+ Checked if the old CPU had any bent pins up and to my eye they all seem okay.

+ If I put both sticks in A1 and B1 the system posts with 16GB showing on windows.

 

[pctech2005]

It seems the issue might be a defective motherboard, do you have any warranty left on it?

 

[simpledude]

Almost certain that the motherboard was the issue too, I didn't have any warranty on it more than likely. (over 3 years since the purchase)

Update on the issue, ended up replacing the motherboard, RMAing the CPU (to not take any risks). The system is all good now.

I might be able to figure out what's wrong with it or use it as a test bench in the future.

Thanks your reply!