I followed the same tutorial when I did my RFM without any dramas.

Couple of things to check;

What voltage is the offending power supply set to?

How have you wired up the on switch for the new supply? Maybe try wiring it to be always on.

Hi casperthefriendly
Yep tried it as always on as well, as majority all new PSU's use step conversion I don't have to worry about voltage problems or a switch on the back to change voltage.
Maybe that might be the problem being automatic