What we shall do if the desktop computer makes restart every half minute and no display in screen?

There is many resons ffor this problem, if the computer restart frequently without displaing error message or blue screen, it may be POWER SUPPLY failure.

but if the computer restart just before OS startup, it may be software problem.

This might be overheating, just open the side cover and try to clean with air blower, or remove the heat sink and paste some thermal glue, or better to take to nearest specialized PC Clinic or Authorize Service Center.

  For Display first of all check the power cable & machine is starting or not second check RAM  third check processor Lastly Check the bridge is over heating

RAM and Supply problem and Processor problem 

Hello,

This might be overheating, just open the side cover and try to clean with air blower, or remove the heat sink and paste some thermal glue, or better to take to nearest specialized PC Clinic or Authorize Service Center.  

This problem can range from  faulty /loose memories or operating system /software problem 

 For Display first of all check the power cable & machine is starting or not second check RAM  third check processor Lastly Check the bridge is over heating . thank you ........................