Question CPU light on motherboard

Jan 4, 2021
Hi, I was wondering if anyone could help me out

I turned my PC on recently as I normally would to find that it wasn’t booting, the system fans are spinning as well as the CPU fan however the CPU light is present on the motherboard. THE GPU fans are not spinning.

I have tried all the recommended fixes for this such as resetting the CMOS, taking the CPU out and changing the thermal paste, removing the 8 pin CPU cord from the motherboard and the same cords from the PSU and plugging them back in and playing around with the DIMM slots to ensure it’s not a DRAM issue however I still can’t bypass the CPU light and the system won’t post.

I wasn’t doing anything overly demanding on the computer the last time I used it (such as gaming) and I haven’t overclocked the processor so I’m not sure how it would be fried. The CPU did not have any bent pins and didn’t look burnt what so ever when I took it out and cleaned it.

Is anyone able to advise what else I could try? Or whether they think this could be the processor that’s gone or something else such as the Motherboard?

Thanks, specifications below:

CPU: Ryzen 7 3800X
Cooler: Be Quiet CPU Cooler
GPU: MSI Radeon 5700
Motherboard: Aorus Elite B450 Gaming
RAM: 2 x Corsair 8GB 3000mhz


You forgot to mention the make and model of your PSU. please include the age of the PSU as well. Be Quiet! make a number of coolers, which one do you have? As for your rams, which slots are they populating on the motherboard? When resetting the CMOS, did you disconnect from the wall and monitor, pressed and held down the power button for 30 seconds and removed the CMOS battery for at least 30 minutes prior to replacing it?

If you have friend or neighbor who has a B450 or B550 chipset motherboard with the latest BIOS updates, then you can test your processor to see if that's given up the ghost.
Jan 4, 2021
PSU: Seasonic M12II-EVO 520W
CPU Fan: Be Quiet! BK010 Shadow Rock Slim CPU Cooler

I actually also have 4x 8GB DIMM’s so ideally each slot would be filled, however I have had issues with DRAM not allowing for post in the past so I found myself just using slots 1 and 3 as the PC wouldn’t boot with all 4 DIMM’s in, this isn’t fault of any of the DIMM’s themselves, each has been tested separately in each slot and the system does post with any combination, except when all 4 are plugged in.

2 are Corsair 8gb RGB 3000mhz
2 are Corsair Vengance 3200mhz

To answer your question about the CMOS reset, with the CPU light present on the motherboard the power does not cut out by holding the power button on the system therefore the PC was switched off from the wall, disconnected from all peripherals, monitors and power cords and then the battery was taken out for way over 30 minutes.

Lastly, testing the CPU in a different system was my next plan however I’m currently unable to find anyone who has an AM4 socket in order for me to test my CPU in another system

Thanks for your help