TE0720 - EMC radiation problem (supply circuit)

[StefQM]

We are using the TE0720-03-2IF (with Zynq XC7Z020-2CLG484I onboard).  Unfortunately, compliance tests are failing for radiated emission. 

We've been able to determine that a main root-cause seems to be the power supplies based upon the Intel EP53F8QI on the TE0720 board. These DC/DC converters radiate heavily in a spectrum from around 100Mhz up to 350 Mhz. The plot below shows in blue the bump in the frequency spectrum generated by the DC/DC converters.

Is this something anyone recognizes and have any experience in finding a solution ?