Another option you can try is go into the service menu and select the "burn in" option, let it run through it and watch if it resets.
if it does reset then try the burn in a few times to see if is resetting at any particular function or just randomly
Once you have exhausted all other avenues check the following.
as mentioned check all the wires on the plugs make sure that all the wires are seated into pins on the connector housings properly. I would be concentrating on the ones on the power supply and mpu board
there is a tool to seat the wires into the pins correctly.
some people use a small flat screwdriver to do this but this can do more harm than good, it can widen the gap in the top of the pins making the contact worse.
If you do find a problem with these connectors for the long term it is best to replace them with new housings and crimp pins
also with the power off and unplugged from the wall power outlet unplug the connectors on the transformer and inspect them for heat damage or loose wires.
And last check the plugs on the power supply & mpu board for cracked or bad solder joints. (on the rare occasion just because it is new doesn't mean it's perfect )
Yes there maybe problems with the fuse clips but the main ones in question here have been replaced with the new power supply
And before anyone says anything negative about my post I have stated to do this only once all else fails
