There are old motherboards with BAD CAPS (see google) that do this. But then you tell us the CPU is incompatible. Did you fix that issue?
The title might seem complicated at first glance, mostly because this issue is really, really strange. No one else seems to have encountered this specific problem. Note: my PC works just fine... but: When I shut down my PC, and power it on again, the peripherals (Monitor, mouse, keyboard etc.) do not power on. Here's the thing; if I shut down my PC again and start it up, the peripherals do power on.
If I restart via Windows, Windows does shut down, but the PC does not, I need to hold down the power button to shut it down manually. After this, when I start the PC, my peripherals power up as normal.
It is also worth mentioning that this started happening after I down-throttled my CPU in an attempt to fix an overheating problem caused by an incompatibility between my CPU and motherboard.

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