The sample that got tested by Jonny Guru was sourced from EVGA, and was manufactured by Super Flower, while the sample that got tested by Tom's Hardware was bought in a retail store. Closer investigation reveals the sample from Tom's Hardware was manufactured by RSY. The over power protection on these PSUs failed in two different Tom's Hardware reviews, so it seems this was not the result of a bad batch.
What's going on here isn't entirely clear. It's normal for companies to use multiple suppliers but either EVGA's quality assurance failed or the company deliberately send a golden sample to Jonny Guru. As TechPowerUp suggests, there's no doubt that units of lesser quality than the sample that got tested by Jonny Guru ended up in the retail channel:
It has subsequently emerged that the sample provided by EVGA to JonnyGuru was manufactured by Super Flower, whose Leadex platform is well known for its performance and high quality. Aris of Tom's Hardware (and TechPowerUp), however, bought their review sample from a retail outlet. The manufacturing of the latter had been outsourced to RSY, with (in this case) a resulting decline in build quality. It remains unclear whether Super Flower outsourced its production, or if EVGA is using multiple suppliers or switched manufacturers all together. Regardless, lesser quality PSUs would appear to be in stores in comparison to what was reviewed at JonnyGuru, arguably the most influential review site for PSUs.Legit Reviews asked EVGA to clear up the matter but received a reply that dodges the main questions:
“EVGA stands behind its full line of products, and the 5-Year Warranty on each B3 power supply demonstrates the confidence EVGA has in the quality and safety of each product shipped. If anyone has questions or concerns, please contact EVGA Customer Service and we are more than happy to assist. In the rare instance that a replacement unit is necessary, EVGA will support with a free Advanced RMA on all EVGA SuperNOVA B3 Power Supplies.In a separate response to TechPowerUp, EVGA mentions they have not received a single customer complaint about the SuperNOVA B3 going faulty under normal operating conditions.
In addition, the EVGA SuperNOVA B3 review samples, as well as the production, were all built at the exact same qualified facility.”