If you’ve either built a computer or bought a desktop computer in the past you’ll know how tricky it can be to set the airflow in the system up just right. You want to manage PC airflow in such a way that everything is chill enough, but you don’t have a hurricane on your desk.
In this article, I’m going to go over the basics of PC air cooling and give you some tips on how to manage PC airflow.
Table of Contents
Setting a Goal
Before we go any further it’s important to understand what air cooling hopes to achieve. The components in your computer generate heat as a part of their normal operations. This heat is transferred to the air surrounding the component by a passive heatsink, an active fan sink or some other method.
This means the air in the case is heating up and at some point, it will reach the maximum capacity for heat it has. Then the component will stop transferring heat to the air and will simply get hotter and hotter until it fails.
So what we want to do is move hot air out of the computer case and bring cool air into the case to soak up more waste heat. This way heat is transferred from the computer out into the room itself.
This means that you need to have specific places in your PC case where cold air will enter and hot ear will exit. A common strategy is to suck in cold air from the front of the case and then expel it at the back. Alternatively, you can have cold air intakes at the bottom of the case and vent hot air out of the top.
In all cases (pun intended) should be able to clearly visualize the flow of air through the case. Cool air should flow over all major components that produce significant heat.
Passive Versus Active Ventilation
Each exit and entrance for air in your case can be actively driven or left without a fan. The idea is to have fans pulling cold air in and to have ones pushing hot air out. However, to cut down on noise or because you may not have enough space it can work to simply have one or the other.
Hot air rises naturally, so it’s sensible to have heat extraction fans in the upper half of the case. Even in the top of the case venting straight out. Cool air is then naturally sucked into the bottom of the case to fill the vacuum.
If you can manage to prevent components from dumping their heat into the case in the first place, this can really help airflow and temperature management.
For example, blower-style graphics card coolers can suck in cold air through a nearby vent and then blow it straight out of the card’s rear panel. Little if any heat from the card goes into the case. Many cases now also isolate airflow for the power supply too!
Similarly, using an all-in-one watercooler on your CPU allows you to transfer CPU heat through water pipes directly to a side vent without entering the case as a whole. This means that the case airflow now only has to cool low-temperature components such as the RAM, motherboard chips and drives.
Clearing the Air
The other key to having good airflow and making sure there are no dead spots where air doesn’t flow and heats up is to practice good cable management. Many modern cases have a little clip which you can snap excess cable into.
There’s also the option of using sleeves or cable ties. Many modern power supplies are equipped with modular or semi-modular cabling. This means you can detach non-essential power cables store them elsewhere.
Porting your cables out of sight is one of the most effective ways to maximize airflow and it means you don’t need as many fans or so much fan noise.
My Biggest Fan
Fan choice is also pretty important. Larger fans tend to be quieter because they don’t have to spin as quickly for a given amount of airflow. A good balance is a 120mm fan. Pay attention to the airflow direction, which is indicated by a little arrow molded onto the side of the fan.
Dust to Dust
Even if you design a really efficient airflow for your computer, the buildup of dust will get worse over time. One way some builders combat this is by having slightly more intake fans than extraction fans.
The idea is that air is always being pushed out actively from the case and that the air pressure inside will be a little higher. This theoretically prevents dust from getting in as much as it would with negative pressure. Whether this actually works is debatable and I don’t put much stock in it.
What does work is to have dust filters over the major intakes of the case. This means you only really have to clean the filters periodically and much less dust will actually make it onto components. Investing in a compressed air spray will make short work of dust in heat sinks and other nooks.
Manage PC Airflow Like a Pro
That covers the basic when you want to manage PC airflow. Air cooling is going to be around for a long time yet, even if some interesting alternatives exist. So having the knowledge is totally worth it.
If you follow these basic rules and tips there is no reason why you should experience heat-related failures ever again. You can manage PC airflow without much effort as long as you plan well. Be sure to check out our guide on CPU AIO water cooling and on how to budget new PC builds.
If you need help finding the best liquid CPU cooler check here!
Lead Image By cappie2000 (Modelled & rendered with Lightwave 3D) [Public domain], via Wikimedia Commons
Airflow Image is Public Domain via Wikimedia Commons
Girl with duster image is Public Domain via Pixabay