The VRM on the C9Z390-PGW might only have six phases, but it was able to handle our overclock to 5.2GHz, we still recommend cooling fan pointed at the VRM. The six-phase VRM is capable of supporting the OC because of its quality level. Supermicro is also using the more expensive Texas Instruments re-drivers for USB 3.1 ports. They didn’t cut corners where they could have.
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