Abstract: A car seat heater has an improved energy efficiency, which includes a heating wire which is coupled to a car seat and includes a metal-plated carbon fiber, a seat temperature sensor configured to detect temperature of the heating wire, and a variable temperature controller configured to control temperature of the heating wire according to a diameter of the metal-plated carbon fiber and a thickness of a plated metal thereof.

Abstract: A computer system including a main circuit, a main cooling fan cooling the main circuit, a detector detecting a driving state of the main circuit, a power supply which supplies driving power to the main cooling fan, a second circuit, a second cooling fan supplied with driving power branched from the driving power supplied from the power supply to the main cooling fan to cool the second circuit, and a controller controlling the power supply so as to supply the driving power to the main cooling fan based on a detecting signal from the detector. Thus, embodiments of the present invention provide for a computer system that does not require separated controlling circuits driving of separate added cooling fans, including a main cooling fan, but through a controlling circuit that controls driving of the main cooling fan and an additional added cooling fan, thereby improving layout efficiency and decreasing manufacturing cost.