Solved
Decoupling capacitors in STM32F4 scheme.

Are the VCAP_1/VCAP_2 external capacitor decoupling capacitors ? (when using the 2.2 uF with power regulator ON)
PowerSupplyScheme page 77:

Are the VCAP_1/VCAP_2 external capacitor decoupling capacitors ? (when using the 2.2 uF with power regulator ON)
PowerSupplyScheme page 77:
Yes. The MCU generates its own vore voltage and this voltage _needs_ decoupling.
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