what is this siren for?

hi.
I was cleaning the CPU fan because it was full of dust,after installing it back I forgot to plug in the plug of the fan when i turn on the computer i noticed the fan was not on so i pluged it in while the compute was on but i got a massege telling something like '' CPU was shut down due to thermal event(over heat),service the unite to solve this "
I opened again and cleaned it again ,but now when i turn the computer a siren goes on and computer shuts off by itself after desplaying this massege.

any help?

 

Did you plug in the fan?

 

You may need to read through the manual for your motherboard. See what it says about the thermal settings for your system.

The system (BIOS) may be set for a "Quick Boot "...it only remembers what happened at the last startup. Look at "resetting the CMOS" (read in the manual).

You may just need to reset the system. Hopefully...nothing is fried.

Matt

 

I also thinks so because if CPU was damaged, the computer won't even power on.

 

Thanks guys for your time..
actually there was some problem with the paste between heat sink and (sockate)I think that PASTE was too thick for them so .fan couldnt cool down the CPU after cleaning now its working....but sometimes my computer freezes (I dont know if its because of that PASTE),other then that computer is working fine.