Control fans on Apple computers, also on Windows via Boot Camp. Monitoring of fan speed and temperature sensors. Solve fan noise and overheating problems, iMac HDD replacement
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If we ask about how a component is powered, there is a reason. If you don't know, check it. The 8 pin power connector should go to both mini 6 pin ports of the backplane. If it is underpowered, it will let the machine shut down hard on heavy GPU load.