Howard means a surge-protector, which will be connected between the wall-socket and your PC. Pakistan probably does not have a steady voltage, such as always 110V or 220V, in the morning it might be 180V, at lunch 210V, around teatime maybe 250V.
If your country supplies normally 110V, anything over 120V is deadly for a PC.
If your country supplies normally 220V, anything over 240V is deadly for a PC.
Does the setting in your PSU match what you get out of the wall?
E.g. if your wall-socket supplies 220V and your PSU is set for 110V, sure enough it will burn out quickly.