What Is a Processor Cooling System and Why Do We Need One?
Just like GPUs, CPUs can run hot! Anything between 50-80 degrees Celsius is typical, depending on what the CPU is doing.
To keep the CPU from overheating, it needs a cooling system, ranging from a simple block of metal (a heatsink) and a fan to draw the heat out of the processor to a liquid cooling system.
Just as for GPUs, a CPU’s specification will include its thermal design power (TDP). This value can help you choose a suitable cooling system.
Thermal Contact
A thermal interface material (TIM) (a metal block or a pipe-based system for liquid cooling) is placed between the CPU and whatever is clamped to it to ensure good thermal contact. The TIM may be a very thin layer of thermal paste (also called a thermal compound) or a thin, flexible thermal pad. Sometimes the TIM comes with the CPU or the cooling system (see next section), or you may have to buy it separately.
Without a TIM, CPU cooling will not be as efficient, leading to slow performance or unexpected shutdowns if the CPU overheats. For similar reasons, never run a modern CPU without a heatsink because the very rapid temperature rise can damage them.
Retail vs. OEM
Retail-packed CPUs come with a heatsink and fan, but you can also purchase just the CPU (known as the original equipment manufacturer or OEM version), for which you must purchase a separate cooling system.
So why would you buy the OEM version of a CPU if you don’t get a cooling system with it?
There’s a few reasons for buying the OEM version of a CPU:
They can be cheaper.
The retail version of the CPU might be out of stock.
They allow you to get a bigger cooling system for PCs that require processor-intensive tasks or a higher clock speed (if the CPU and motherboard support overclocking) to squeeze out some extra performance.
You might be replacing a faulty CPU and already have the cooling system.
Checklist
Here are the key points to remember when choosing a processor cooling system:
Will a stock cooler do? If a stock retail cooler is provided, it will probably be sufficient unless the user runs high-performance apps on the PC/Processor.
Do you need to purchase a separate cooler? If there’s no stock cooler, look up compatible footprint ones on suppliers’ websites and then verify that it’s suitable. For example, check the cooler’s maximum supported thermal design power (TDP).
Will it fit the case? Check the cooler dimensions - some are very tall and won’t fit in a slim desktop case. You may need to revisit this point once you’ve chosen a case.
Consider liquid cooling. The block that fits on the CPU with a liquid cooling system can be quite slim and suitable for smaller cases, but check that the associated fan assembly will fit.
Do you need any thermal paste or a pad? Does paste or a thermal pad come with the CPU or cooler?
Your Turn!
🎯 Once more, it’s time to go shopping.
⚙️ You’re after a cooling system that’s suitable for your CPU. See what you can find, and, once again, also pick out a cooler that’s less suitable. For both cases, note the reasons for your choices.
✅ Once you’ve finished, see how your selections compare with mine in the Example Solutions document: .docx / .odt.
Let’s Recap!
CPUs get hot and need to be cooled.
There’s a whole range of cooling systems available, from simple metal blocks to liquid cooling devices.
Some CPUs come with a heatsink and fan, which is generally suitable for the job.
You need to purchase a stock cooling system if one isn't supplied.
The cooling system must be the right type for your CPU; otherwise, it won’t fit properly. Also, make sure it’ll fit in your case.
Great! We now have something to run the display and a suitable CPU that’s not going to overheat. We still need a few more bits to assemble a working PC.
