cooling system

thermal

paste

CPU

Great news! The long-awaited i13900K CPU has finally arrived and you are trying

to build a new desktop with it. Before getting your hands dirty, you want to know if

your existing cooling system will work with the powerful 13th generation intel CPU.

Your cooling system uses a heatsink mounted on top of the CPU as shown. A layer

of conductive thermal paste is used between the heatsink and CPU to minimise

thermal resistance.

Assume the thermal paste layer perfectly fills the entire gap between the chip and

your cooling system, and has a thickness of 2mm and conductivity of 9W/mK;

and your cooling system (not including the paste) has an Overall Heat Transfer

Coefficient, U, of 1,527W/m² K based on the surface area of the base plate.

Also assume that heat is generated uniformly and steadily in the CPU.

If the dimensions of the chip's top surface are 45mm x 37.5mm, the ambient

room temperature is 21°C, and the CPU temperature is 98° C, estimate the heat

flux (kW/m²) up through the top surface of the CPU and through the cooling

system.

Hints:

Even though the heatsink in your cooling system has fins, you do not need to use fin

analysis here since you are given the Overall Heat Transfer Coefficient. See Slide 8

of the lecture video slides.

The surface area of the base plate used to specify U is the same as the area of the

top surface of the chip.