No, it's actually not. It's actually pretty decent for the price, but I already changed it for a better one when I removed the cooler earlier as I saw the same thing you did. I also chose a much better memory module.
Aris says that power supply is fine, and if he says it's fine, it's fine, because there is no higher authority when it comes to power supplies as far as I and the rest of the PSU community is concerned.
https://www.techpowerup.com/reviews/Silverstone/ST50F-ES/11.html
So thanks for the input, unfortunately it's not accurate. And, I changed the PSU probably about the same time you posted your build anyhow. Not many options in NZ and they are all expensive options. If the OP had to use the lower priced Silverstone unit, he actually could with no problem.
PCPartPicker part list /
Price breakdown by merchant
Power Supply: Silverstone - 500 W 80+ Bronze Certified ATX Power Supply ($99.95 @ Computer Lounge)
Total: $99.95
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-12-21 20:03 NZDT+1300
But the TX is a much better unit.