That header can power up to two case fans, which then take orders from an on-card hardware controller that monitors five temperature sensors on the graphics card’s PCB to ramp fan speeds up and down as needed.
Turbine-X adds a PWM fan header to the rear end of the card’s custom PCB, similar to what you find on ROG Strix graphics cards that support Asus’ FanControl technology. Sapphire is also introducing “Turbine-X” with the Nitro+ Radeon RX 64 Limited Edition. The fans support Sapphire’s Fan Check and Quick Connect initiatives, allowing you to check their health in Sapphire’s Trixx utility and quickly pop out individual fans if one needs replacing.
They won’t kick into action until the GPU temperature hits 55 degrees Celsius, and since the Nitro+ Limited Edition doesn’t get anywhere near that hot except during gaming, the card stays utterly silent during normal desktop use, unlike reference Vega cards. Not one, not two, but three large fans sit atop the heatsink.
