Overclocking is not supported, so i would recommend running your system at stock settings in the bios to ensure stability. Can you tell us more about the flickering, was it occurring in the motherboard bios or once Windows loaded? If it was the latter, it may be unrelated to the CPU.
The overclocking settings triggered a default CPU frequency of 1.4 GHz. MSI mobos in particular do not support overclocking well if at all in most cases.