Questions
Q1
Why my motherboard keeps turning on and off multiple times?

When first boot up your system or install new CPU/RAM, BIOS will scan the system for new devices. The scan will reboot up to 3-5 times, after finished initial boot up process BIOS will remember the settings and fast boot up with no reboot hereafter. (clear CMOS will reset BIOS to default setting thus cause the same reboot behavior)