12700K, 4x8 3200 c16 corsair dom plat, z690 Aorus elite ax ddr4, Palit 3060ti, rm850x.

My pc has a problem. Every now and then, my computer will refuse to post, flashing CPU and DRAM lights alternating for some time before shutting down after some time to retry post.  This is usually fixed by reshuffling my ram into many different combinations until something finally works. This was always an inconvenience but it always fixes itself before I do further troubleshooting. One thing I have noticed is, this always happens if I do not turn on my pc for more than a few days. This does happen even if I turn my pc on everyday, but this also always occurs if I don’t turn it on for more than a few days.

This time, nothing works. No ram combination works, even single stick. However, a new combination of post lights has appeared, flashing CPU, DRAM and then VGA once before the computer completely shuts down. This does not rectify itself. It happens with some combinations of ram sticks. I have unplugged my GPU and run off iGPU with same problem happening. Have also reseated all the things I could reseat. Resetted CMOS a million times. Flashed BIOS to have same problem.

I have replaced most of the parts in the PC before, with similar issues. I have had a GSkill and an Adata kit before with the same issues happening, have also switched my motherboard before from a Z690 Aero G. Same problem ever since I built my pc. Only components I haven’t switched are my PSU and my CPU. 

This leads me to suspect my i7. I pre ordered this in 2021 when it was announced, so this would be an early batch of Alder Lake. Could my CPU be defective and finally threw in the towel? This is my last troubleshooting call for help before going down to a shop. If needed, I may jump ship to Zen 3 because of my ram. What other troubleshooting steps do you recommend?

Video shows alternating CPU DRAM. Can’t attach the video with VGA because only 1 attachment is allowed.

Pc that can never post.