Black screen, CPU 100 degrees

[mgscolieri]

Asrock H81
Ddr3 1600 mhz 12 GB
GTX 960
i5 4460 aftermarker Cooler master cooler

Ok so build this PC for my little brother that worked flawlessly for 2 months.
Have been checking temps and the cpu have been at 70 at max load and gpu at 70 aswell. Been running Msi afterburner all the time.

Then when i visited him the other day he was playing fortnite and the cpu was running at 100 degrees!!!

I immediately checken bios and saw the temperatures there so msi didnt read wrong, which it didnt.

I pulled the cpu fan and checked cooling paste and the mounted it correctly again. The first time i did this i got a black screen when restarting. which iam stuck at.

My brother thinks its my fault bc i pulled the fan and broke his pc. I do not think i did something wrong.

Did the cpu die bc of overheating?
All the fans are running but its just a black screen. Tried different monitors and cables. no signal

 

[PuperHacker]

Could it be that the cooler was malfunctioning? Do you have warranty for either the CPU or the cooler? What were the temps of the other components during this failure? Have you checked the voltage?

 

[dshort01]

Could it be a bad monitor or video card? Isolate the issue by testing.