Question most probable culprit preventing cpu from posting

[fivefootwall]

On my Gigabyte 970-UD3P with bios FB, I managed to run my FX8350 for several years. Then it wouldn't post. Replacing the 8350 with a 6100 posted OK, but the 6100 does not have the processing power necessary to run Cakewalk by Bandlab and all that entails. I purchased another 970-UD3P board with another 8350 installed, replaced the 6100 with that cpu, and again it would not post. I purchased another 8350 used, but need some suggestion as to how to proceed logically. I'm running Windows 10.

Seems odd that 8350s fail to post but the 6100 still does OK. I understand that the 8350 requires more juice than the 6100, but now that I am in the "throw parts to repair" mode, so would most likely culprit be Power Supply, motherboard, or something else? I ran 2 hour Memtest on memory with 6100 installed and NO errors. All the voltages from the Power Supply report as they should using CPUZ, HWMonitor, and Open HW monitor.

I have a used, "supposedly OK" 970 UD3P motherboard spare, but needlesslyreplacing MB is a pain I'd like to avoid. Purchasing a new computer poses issues for drivers and apps on my C: boot drive; I'd have to stick that drive into the new computer and pray. Suggestions folks?

 

[faalin]

What PSU do you have, make and model, are you using a 8 pin for the CPU or only a 4 pin? If the PSU is as old as the motherboard i would say replace it.... they dont last for ever.

 

[fivefootwall]

Enermax ECO80 EES620AWT, same age as MB, believe first came out from Enermax in 2009, so ~16 years old. It has 8 pin for CPU.
Hmmmm. So when PS get old they can't manage as much 'sauce' as when new? So when not pushing it with the 6100, it works OK; but with the 8350 takes a doo-doo?