When using a high speed AMD CPU together with the boxed fan, why is my system unstable and sometimes shuts down automatically? A: This could be caused due to CPU overheating, and the reason is because the CPU fan is not seated properly and is not fully in contact with the CPU. Gigabyte motherboard has thermal protection designs, which will shutdown the system automatically to prevent the CPU from burning. Suggestions:
Please remove the fan and reseat it again, but this time please completely remove the pink thermal pad from the heat sink and then apply a think layer of thermal paste heal dissipating gel. Make sure the CPU is making full contact with the heat sink.