Thermal paste improves computer cooling systems by enhancing the transfer of heat from the CPU or GPU to the heatsink. This paste fills microscopic imperfections between the surfaces of the chip and heatsink, reducing air gaps and improving thermal conduction. By ensuring efficient heat transfer, thermal paste helps maintain optimal operating temperatures, preventing overheating and ensuring stable performance. It is essential for prolonging the lifespan of components and maintaining the overall reliability of the system, especially in high-performance computing environments.