Computer keeps shutting down!

Every time i turn my computer on it will turn off and back on around 3 times and then it will start working properly.
I opened my computer up and cleaned it then i powered it on when i turned it on my motherboard had 4 lights on and one of them was red and the rest were green.
I changed the power cable on my computer to see if the cable was faulty. I have googled this problem and have found no answer.
Answer #1
turn off and back on around 3 times
it cycles to what point before restarting ?
you see the BIOS screen ? or nothing ?
try pulling and replacing any cards or memory to reseat them
you could also try a BIOS reset with the “RESET_CMOS” jumper on the motherboard
Answer #2
Would that change anything on my pc that could harm it?
Answer #3
Would that change anything on my pc that could harm it?
no, unless your not careful and break something
Answer #4
Could be overheating. How old is it? Maybe some new thermal paste on the heat sink will help. It can be a number of problems. Try “Speedfan” install it and check your temps inside.