As mentioned, motherboards vrm isn't really meant for 125watt TDP cpu's so might be that. Think that FX 8350 isn't even in the support list, although the 8320 is, which is a 125Watt TDP cpu also. The VRM doesn't even have heatsinks which is a kinda bad sign.
They should have marketed this one as purely for 95watt TDP cpu's.
A watercooler will make this only worse since no active airflow over the vrm anymore. You really would want to point a fan onto that or better get a good top down aircooler.
Then that psu is low quality. Only way to know for sure is test with a beter one.