Overclocking performance was fine but, somewhat surprisingly, was not as strong as the ATX B350 Tomahawk. That’s despite the power delivery solutions being practically identical, except for an additional heatsink for MSI’s ATX part. Our chip would not hit its 4050MHz limit with the B350M Mortar, which is the same outcome we have seen from Gigabyte and ASRock B350 offerings at this price point.